Avoiding interference building a repeater

[WSCV533]

Hello all, probably got a stupid question for y'all to make fun of. I am slightly new still to GMRS. I got my Callsign about 3 months ago now. I have a simple 20' flagpole antenna and get good (~15 miles) simplex range for my needs. I'm trying to figure out how to avoid causing any interference when choosing what channel to set on my new repeater. There's a lot of repeaters within my range and my thoughts were on RP22 or 462.725 . I have not received anything on this channel and on the map the closest repeater to me that's on the same channel is about 50 miles away. I have tried keying up using the ctcss tones and get nothing, which leads me to believe it is out of range. I want to avoid disruption as much as possible out of respect for other GMRS operators. What's a fool proof method of avoiding interference? Obviously I will use "privacy" tones but is there more I can do to keep the air waves clear. I am almost ready to turn on my repeater system, but just wanted to ask this before I do.

[SteveShannon]

I think you have done everything you could. And kudos to you for being considerate. 

[WSCV533]

20 hours ago, WRXP381 said:

Sounds like you already have it figured out.   Also sounds like you dont really need a repeater but many people build them and they never get used.     if all you’re getting is 15miles then why bother with a repeater it’s not going to do very much.  
 

On Southern California we have many huge repeaters and they all get in the way in some way or another but no one owns the air waves and chances are you won’t really interfere much at all.  

Because all I NEED is 15 miles... Sure I could go up 50, 100, 500 ft, but then interference would be worse, and I would have way more coverage than I NEED.... This'll be a family repeater, only need to talk so far. And it's about 3 times the distance I get with HT to HT simplex range.

[Socalgmrs]

Sounds like you already have it figured out.   Also sounds like you dont really need a repeater but many people build them and they never get used.     if all you’re getting is 15miles then why bother with a repeater it’s not going to do very much.  
 

On Southern California we have many huge repeaters and they all get in the way in some way or another but no one owns the air waves and chances are you won’t really interfere much at all.