Be aware that the photos are nearly always more flattering than the real thing. And owners are too often ignorant of actual condition and some will outright lie or evade. The photos look about what I would expect from a 29 year-old coach - a bit tired. I see cosmetic defects on the exterior and wear inside, so the amount of care it has had is average at best and maybe not even that. Low mileage is common on motorhomes, but doesn't mean it's in great condition. The roof looks black and maybe worn (I can only see a small area), and the condition of the caulking (seams and around openings) is an unknown. Roof caulking defects are the major source of water leaks.
Tires and batteries are major expense items and usually poor on an old, cheap RV. A 7-10 year old tire is a time bomb even if it has good tread and looks ok. Batteries can show adequate voltage but lack stamina (amp-hours of use). 6 big tires and 3-5 large batteries can put a huge dent in your budget.
Engine and transmission are big ticket items but you can usually quickly assess whether they are in working condition or not. What is harder to guess is if they have any imminent failures. Even a mechanic can have a tough time predicting that. Clean oil & tranny fluid is a positive indicator. So is the availability of service records.
Much of what you need to worry about is the same as buying a house. Look for leaks inside & out, soft spots in floors, ceiling & walls, condition of appliances and plumbing/electric systems, etc. Furniture wear & tear should be obvious, and cabinets too. Check them all closely, though.
The price is in line with what an old & tired coach is worth, assuming no major flaws. If in nice clean condition it would bring $12k-$15k, but worn & tired is more like $5k-$9k. Personally I'd rather spend more to find a real jewel, but it usually takes a lot of searching and some luck. In any case, have another $2.5k-$5k in reserve for first year repairs. BTW, you will be shocked at RV shop repair costs. They get $120-$160 per hour and aren't bashful about the labor hours they claim. And they tend to throw expensive new parts at everything rather than fix or adjust. Quality of work is often dismal as well.