Alright. Since I am the guy with the tens of thousands of dollars setup and the commercial install I believe I need to interject here. Never did I say that a small repeater system is useless. And there are COMMERCIAL repeaters available that ARE indeed two mobiles in a box with a controller between them. And those work find if that is all you need.
My point was if you are going to put up a big commercial grade install that you need to NOT pull the crap of wanting fee's paid for access, as this level of install has a huge footprint that will interfere with other repeaters on the same frequency in that footprint. And the frequency resource is limited for repeaters. I am all for guys that want to put up a repeater on their roof or short TV tower and be able to talk 8 or 10 miles. This sort of thing SHOULD be encouraged. But you still need to be aware of others on the frequency and try to find a quiet pair to set your repeater up on.
The other thing that needs to be said here is IF you are going to stick an antenna WAY up in the air and cover a 60 to 80 mile radius, you DO need to have good commercial equipment and not two portables with a back to back cable between them and a cheap duplexer. And here's the reason. If you are the only one that will be using it, and the usage is light, it don't matter. But with a big coverage footprint there is a good chance that it will see a lot of use and portable radios are NOT designed to be run at that duty cycle. The commercial repeaters I use for GMRS are 100% CCS (continuous commercial service) rated. This means they are designed to be transmitting up to 100% of the time, 27/7/365 and live. If you were to try that with the two back to back mobiles the transmitter would not survive the abuse, even with a fan and additional cooling. Now, my repeaters are only logging 30 to 45 minutes of use a day currently... but that number keeps increasing. And that's fine. I built it to run all the time, and offer it for free to all licensed users in the coverage area to use at their leisure. But I would hate to see someone put in inferior gear at some remote site and it die when it was needed. That situation is actually worse in my mind than it not being there at all. Because if it's needed and expected to be operational. And that operational repeater is part of someones emergency plan, then it needs to work as such.