Hi JakeJenny... and welcome.
There are a myriad of things to look for when purchasing an RV so I'll touch on just a few. There are some extremely knowledgeable RVrs here - some I'm sure with Georgie Boy-specific knowledge whom I'm sure will chime in, but there are some generic things to consider.
I would strongly recommend having an independent (chosen/paid for by you) knowledgeable mechanic go over the drive-train. A pre-buy inspection certainly won't guarantee that there's nothing wrong with the drive-train, but a knowledgeable mechanic might find something wrong, or something that's about to go wrong (i.e. expensive).
Look in all the overhead cabinets for indications of water leaks (stained roof, warped wood cabinets etc).
Look at the age of the tires (stamped on the tires themselves). When tires get to be 6 or 7 years old, you should plan to replace them soon - even if they LOOK okay. (There are lots of postings on this site about tire age issues).
Operate EVERY system in the coach to make sure they work. Run the generator under a full load (all A/Cs) test all the lights (inside and out), check the heater(s), operate the fridge (freezer and fridge), make sure the steps retract, the backup camera works (if it has one) - you understand - everything.
I'm not suggesting that everything has to work as it did when it was new - but if something doesn't work it may give you some wiggle room from which to bargain. Replacing a coach's tires, for example, will likely cost a couple thousand dollars. Repairing/replacing a LP fridge, hundreds (or more).
And of course, drive it. Take it out onto the freeway and see how it drives (a good time to test the cruise-control). Don't be alarmed if it feels... different than your car or SUV, but you shouldn't be exhausted when the test drive is over.
Keep us posted on how it goes, and good luck!
Kev