I would run the LLC and we would need to determine ownership %s

You will have a hard time remotely running 15 spaces  with the expectation of  a third part manager.  

I plan on keeping the property for the long run.  

I worry that people will be inconsiderate about usage, running partial loads while others are waiting, etc.

Water heaters in Az Run about $400-$500 (12  year warranty, 40Gal, $499 at Home Depot) , and I can install it myself

you may be running into the negative perception of wholesalers who tie up property with no means to actually close. and if they cant assign the contract they walk . 

Also I think if I compare equal amounts of hard work at my job vs. running a real estate investment business, I will make more in the latter.

My name is Juan Rosado and I just moved to Dallas Fort Worth (DFW) to work as a civil engineer.

If it's below 10 homes rented last month run.  

Everything is finally in order and now I want to run at least 1 campaign before the big day to get the ball rolling again and possibly knock down a couple nice deals to help foot the budget :-)Anyways to the topic at hand...We have always used Yellow Letters . com to handle our marketing and so far the response has been about 2-3% - majority seem to be "tire kickers," so we are considering a little different approach.