You need to put down a bit more info to get help. As your budget is on the low side, try these for starters:
1. What condition can you accept? $5k (or less?) will usually get an FGRV in need of a bit of work, a good clean-up and minor repairs. tires
etc at the very least
2. Is Older OK? That price range usually dictates at least a 15-20 y.o., but it's condition not age that's important.
3. What features are a "Must Have"? a/c, bathroom, water heater, fixed bed, etc.
4. How many do you need to sleep
5. What will you be towing with.
Fill in the blanks and help will be at hand....