Radioguy7268

Assuming you do not own the repeater, you should ask the repeater owner if the system is capable of multiple PL groups.  That type of setup was commonly used back in the day for Community repeaters, where each user group (plumber, HVAC, Landscaper, etc.) had their own PL tone, but they all shared a common frequency, and each user had to monitor to make sure that the repeater was not in use by one of the other groups before they would Key up on their PL.
If the repeater has Multiple group capability (Every Kenwood TKR-850/851 came with that feature right out of the box) then it's simple to just request your own separate PL tone for your group.  Expect to pay for that feature if it's available.  Listening to a repeater's output in Carrier Squelch would defeat the purpose of having a separate PL tone. Set up properly, your daughter would only hear you when you keyed up using the special PL tone. Other traffic on the repeater would be nothing but a flashing receive light on her radio.
It's 1970's technology, so don't expect any actual privacy or miracles - but it would do what you're asking for.

I'm sorry, but if you're using a Baofeng (or other CCR with a Direct Conversion receiver on a Chip) then  you're missing half the show if you're just focused on transmit power & ERP.
The real game is played on receiver selectivity & desense. Sure, the CCR's have some good/great specs (on paper) for sensitivity in a laboratory testing environment. They fall short when you start looking at adjacent channel rejection and desense. Stuff like that matters in the real world. Measure your Signal to Noise and Distortion and now you've got something worth measuring on the receive side. Do you have tools that can generate a low level calibrated output to test receiver performance?
10 watts in a handheld looks great on paper, but it doesn't take into account how well the other party receives. I'd rather have lower ERP with a more selective receiver that can actually pick out a desired signal at -120 dBm & recover it into understandable audio. If your CCR is still sitting silent in the presence of a -114 dBm signal, you're missing out on more than 6 dB in the math of Signal to Noise. The ERP side says you'd need to quadruple your transmit power to achieve the same S/N ratio.
Take a look at the Motorola XPR "e" series and the Vertex EVX radios if you want to see what a SDR chip coupled with good electronics and a little filtering can look like. Heck, even the older CDM mobiles had great analog receivers with some nice audio.
Focusing on transmit power alone is missing half the equation.

Going back to one of my old experiences when I worked for Motorola years ago...
A small city police department had a failure of their old GE repeater they had been nursing along for many years, so they needed a new one. Budgets were tight, but they insisted on a 100 watt unit. Now, the repeater was naturally on a hill, on a water tank, and was at the highest point in the city, and no more than a mile from the city limits in any direction. They wanted 100 watts. VHF, carrier squelch mind you...and 100 watts. 
While they waited for a new repeater, we loaned them a Desktrac (not what you need for public safety, but it'll work in a pinch). 
Once on the air, the asst chief said, man, that sounds good. And the range is great, can we just keep that one? Is it 100 watts? 
Sure, it's 100 watts. 
It was in fact 25 watts..... no one could tell. They later got a new repeater, but we still didn't set it up for 100 watts. 
Point is, don't get hung up on wattage, use what works for the situation you need it in. 

I'm sorry, but if you're using a Baofeng (or other CCR with a Direct Conversion receiver on a Chip) then  you're missing half the show if you're just focused on transmit power & ERP.
The real game is played on receiver selectivity & desense. Sure, the CCR's have some good/great specs (on paper) for sensitivity in a laboratory testing environment. They fall short when you start looking at adjacent channel rejection and desense. Stuff like that matters in the real world. Measure your Signal to Noise and Distortion and now you've got something worth measuring on the receive side. Do you have tools that can generate a low level calibrated output to test receiver performance?
10 watts in a handheld looks great on paper, but it doesn't take into account how well the other party receives. I'd rather have lower ERP with a more selective receiver that can actually pick out a desired signal at -120 dBm & recover it into understandable audio. If your CCR is still sitting silent in the presence of a -114 dBm signal, you're missing out on more than 6 dB in the math of Signal to Noise. The ERP side says you'd need to quadruple your transmit power to achieve the same S/N ratio.
Take a look at the Motorola XPR "e" series and the Vertex EVX radios if you want to see what a SDR chip coupled with good electronics and a little filtering can look like. Heck, even the older CDM mobiles had great analog receivers with some nice audio.
Focusing on transmit power alone is missing half the equation.

I'm sorry, but if you're using a Baofeng (or other CCR with a Direct Conversion receiver on a Chip) then  you're missing half the show if you're just focused on transmit power & ERP.
The real game is played on receiver selectivity & desense. Sure, the CCR's have some good/great specs (on paper) for sensitivity in a laboratory testing environment. They fall short when you start looking at adjacent channel rejection and desense. Stuff like that matters in the real world. Measure your Signal to Noise and Distortion and now you've got something worth measuring on the receive side. Do you have tools that can generate a low level calibrated output to test receiver performance?
10 watts in a handheld looks great on paper, but it doesn't take into account how well the other party receives. I'd rather have lower ERP with a more selective receiver that can actually pick out a desired signal at -120 dBm & recover it into understandable audio. If your CCR is still sitting silent in the presence of a -114 dBm signal, you're missing out on more than 6 dB in the math of Signal to Noise. The ERP side says you'd need to quadruple your transmit power to achieve the same S/N ratio.
Take a look at the Motorola XPR "e" series and the Vertex EVX radios if you want to see what a SDR chip coupled with good electronics and a little filtering can look like. Heck, even the older CDM mobiles had great analog receivers with some nice audio.
Focusing on transmit power alone is missing half the equation.

No, he wasn't talking about using GMRS to advertise items for sale, but more for business operations ie, Walmart store operations, road flagging crews, survey/construction crews on a work site, provided each user is licensed. Its permitted, but there is a quick return loss between each user and just licensing a business frequency.
One way it would make financial/common sense is a family farm, all workers are in the "family" list if Part 95, then it would be easy (and cheap), and not require coordination, to put up a GMRS repeater and run GMRS for all farm operations. 

If you plan to work repeaters for most of your mobile driving, it's really hard to beat a simple 6" hatpin antenna. They're inexpensive, low profile, and they simply work.
If you're trying to impress the ladies, then by all means, get the longest possible antenna.

If you try to go the legit way for current model software for Motorola, you're probably going to be disappointed. Motorola is not interested in supporting Ham or GMRS at a corporate level, and getting things like Wideband entitlement for CPS software is nearly impossible. The newest CPS2 software for the XPR/Trbo series is not out in the wild, and the older CPS software won't even read new radios fresh from the Factory.
If you are dealing with older model analog radios like the CDM1250 mentioned above, the PM400, M1225, etc.  then there are plenty of unofficial resources and available software, but it's still not 'Plug and Play'. If you are starting from nothing, you would probably be best served to purchase a radio that's already programmed for what you need, and then try to acquire the software & cables to read that radio & save a baseline profile that you can begin to experiment with.

Most folks know when you’re done speaking when they stop hearing words.

Lolwhut? No, I'm not. S-meter calibration is different for HF and VHF. On HF frequencies S1 is 0.2uV, S2 is 0.4uV, S3 is 0.79uV and so on. On VHF it is 0.02uV, 0.04uV, 0.08uV... Why the 10x difference? Because it's not about microvolts at all.
Strength scale (the "S" in the RST):
Faint—signals barely perceptible Very weak signals Weak signals Fair signals Fairly good signals Good signals Moderately strong signals Strong signals Extremely strong signals Where are the microvolts? It is all about acoustics.

12 and 20dB sinad is all I care about. Where does it open and where does it close in CSQ or pl
 

Your using a CCR mobile and your worried about a few watts. Power isn't everything in UHF. Throw an NMO Mount in and hook it up to the radio and use it. That 5 watts will do nothing noticable. 

I don't see any reason, with the right hardware, that a dual pl setup couldnt be implemented similar to what CARLA has on the ham side. One pl, your audio goes to the whole system, while another pl repeats on that machine only. If you key up the local pl, linked audio is muted until a set period after local activity ends, and the link resumes.
http://carlaradio.net/thesystem/pl_ct.php

Who sits around and thinks up this kind of stupidity?  No!  Not just no, but hell no!  This is another hairbrained attempt to make GMRS into "ham radio lite".  I am an Extra class ham, and I am 100% against this.  GMRS (Class A CB) was originally another means of personal (and at one time, business) communication.  It should remain that way.  It should remain 100% analog.  GMRS allows for reliable communication with a short wavelength (think being able to use an ht in a car without an outside or excessively long antenna).  It is great for families, friends, and even properly licensed hams, to keep in touch, especially with family and friends who just do not want to be bothered with testing, radio theory, etc.  If someone wants to enjoy the hobby aspects of ham, play with digital, etc; then let them get off of their dead behind and study and take the tests or shut up! Those who are already hams and who want to turn GMRS into ham lite or other extension of ham radio, please use the privileges you have on ham or upgrade if that is not enough.
People are continuously trying to wreck a great thing that GMRS is with these bright ideas.

Motorola does have RAC for analog, but it's can be scanned.
A better option is to spend the money and get a part 90 license then you have better options.  First is you can run DMR (MOTOTRBO) and run a digital RAC and run basic encryption.  It would also allow you TWO talk paths on the same frequency.  Something that's no possible with analog radio. 
And the other thing with a part 90 commercial license is if others come in, outside of your family unit, they can use the license under your authority.  You can 't grant a non-family member access if they don't have a GMRS license.. so day workers and laborers that are not family can't use the radios. 
The basic encryption will also keep your radio traffic semi-private.  The 6 digit numeric RAC code will keep all but the most determined off the repeater.  And it really sounds like it would be a better option for your specific application. 
The issue is that you are so limited with analog radio.  And there is a greater limitation with the lack of encryption due to the regulations of GMRS.
I know that someone brought up using a trunking controller that would look at radio ID's to grant or deny access to the system, but there again, I don't know the regulations specifically for GMRS would allow that.  Would it work, sort of, until someone with a scanner that could display the LTR data was used to pick apart the information and then it's going to be screwed with if you are really expecting issues with others trying to gain access. 
I wouldn't typically go to these length's but you seem adamant in you post about it to the point you foresee issues before you even have equipment on the air.  And in truth, if you haven't bought any equipment for this yet, now is the time to look at other options that better match your listed requirements.
Personally, I am a P25 and AES encryption guy all the way.  That will always work and NO ONE gets to listen in.  But none of that fits within the rules governing GMRS.
 

It depends on the subscribers and the radios. a CCR radio wont do what you want. Motorola supports RAC (Repeater Access Control) but that's a form of MDC. There are not many options for analog options. I also use DCS for input and CTCSS on output. This helps eliminate many users but isn't a fail safe. 

Another option would be using an LTR controller ,w/that said all of your radios would have to be LTR capable 

The trouble with relying on cellular phones as a primary communication device in an emergency is that every cellular service is over-subscribed by design. They make money on the idea that thousands of people might be in the vicinity of a local cellular tower, but only a few of those people will actually be trying to use their phones at any given moment. In an emergency, everyone picks up their phone and tries to call, text, livestream, or search up: "what do I do in an active shooter situation?"
Any study done in the aftermath of an emergency will point out poor communication as a primary point of failure. Having a dedicated communication system with proper training and protocols is much better if there is an emergency - rather than relying on a service that piggybacks on top of an overloaded cellular service.
Do NOT use Zello for emergency situations.

Layering communication technology on top of a WiFi network is a really poor choice for an emergency communication channel.
When things go bad, you want to count on LESS technology, not more. The more you can adhere to the KISS principle, the better off things will work once things go wrong. Keep it simple, keep it working.
What happens if the school gets hit by high winds that rip the roof off? Well - at least with conventional portable radios, there's the option of simplex. What's the option with Network radios when there is no functioning Network?
There's already money available for schools for communication equipment through Federal/State grants & funding. No need for Amazon.

The trouble with relying on cellular phones as a primary communication device in an emergency is that every cellular service is over-subscribed by design. They make money on the idea that thousands of people might be in the vicinity of a local cellular tower, but only a few of those people will actually be trying to use their phones at any given moment. In an emergency, everyone picks up their phone and tries to call, text, livestream, or search up: "what do I do in an active shooter situation?"
Any study done in the aftermath of an emergency will point out poor communication as a primary point of failure. Having a dedicated communication system with proper training and protocols is much better if there is an emergency - rather than relying on a service that piggybacks on top of an overloaded cellular service.
Do NOT use Zello for emergency situations.

There are lots of funds available for schools under the Safe Schools funding & government grants for security. Take a look here: schoolsafety.gov
I'm not sure why those compact digital Hytera radios are being out-performed by Baofengs, but I'd definitely try out some other radios with better durability & performance specifications. Radios used for safety & security at a school should not be purchased based upon cheapest price. Repeaters are not necessary for most smaller sized buildings, but I've seen some strange stuff with newer construction with low-E glass. There are also advantages to using digital repeaters for a district-wide network that allows
I'd call in a local wireless company & have them survey the building to see what works. They might also be able to help you out with some direction on grants and funding options available to schools in your State.

Layering communication technology on top of a WiFi network is a really poor choice for an emergency communication channel.
When things go bad, you want to count on LESS technology, not more. The more you can adhere to the KISS principle, the better off things will work once things go wrong. Keep it simple, keep it working.
What happens if the school gets hit by high winds that rip the roof off? Well - at least with conventional portable radios, there's the option of simplex. What's the option with Network radios when there is no functioning Network?
There's already money available for schools for communication equipment through Federal/State grants & funding. No need for Amazon.

If I follow what you're asking, you would have radio users on one system (non-GMRS) with the ability to generate traffic on a GMRS repeater. It's not going to be legal.
If you end up relaying their voice traffic from this 'private' system over to an analog GMRS repeater, I also question how 'private' the system would remain. You would be basically be wiretapping your own private system, and then broadcasting the audio over an open analog channel.

If I follow what you're asking, you would have radio users on one system (non-GMRS) with the ability to generate traffic on a GMRS repeater. It's not going to be legal.
If you end up relaying their voice traffic from this 'private' system over to an analog GMRS repeater, I also question how 'private' the system would remain. You would be basically be wiretapping your own private system, and then broadcasting the audio over an open analog channel.

The trouble with relying on cellular phones as a primary communication device in an emergency is that every cellular service is over-subscribed by design. They make money on the idea that thousands of people might be in the vicinity of a local cellular tower, but only a few of those people will actually be trying to use their phones at any given moment. In an emergency, everyone picks up their phone and tries to call, text, livestream, or search up: "what do I do in an active shooter situation?"
Any study done in the aftermath of an emergency will point out poor communication as a primary point of failure. Having a dedicated communication system with proper training and protocols is much better if there is an emergency - rather than relying on a service that piggybacks on top of an overloaded cellular service.
Do NOT use Zello for emergency situations.