As you have seen, each HOA has different rules. Some HOA communities actually cater to winter visitors with RVs. Others, want them parked off the property or in designated areas. Your Realtor can help you find a home with on site RV parking.
For example Robson's Pebblecreek community allows on the property storage in designated areas.
The Realtors have more information on the MLS than a consumer will be able to find on the MLS or Trulia.
Arizona Homes and Land
Please don't rely solely on the MLS listing data as to if RV parking is allowed. I've seen it too many times where an agent mistakenly listed the RV parking without ever verifying this fact. Working with a buyer's agent, they can find out for you which subdivisions allow RV parking and their guidelines for RV parking.
Feel free to contact any local agent on Trulia for this info.
Best of luck!
Here are the 58 CURRENT HOMES FOR SALE that list the possibility of RV PARKING / RV GATE or SEE REMARKS.
HERE IS THE LIST: http://www.flexmls.com/link.html?rlohvm2heyh,12,1
If you have a question about one of the home(s) feel free to contact me.