Tiffin has great customer service and they build a quality coach. Down side is you don't know how well the previous owner took care of things. Sad to say I've seen some fairly new trade-ins that looked like garbage dumps inside.
If it were me I'd be up on the roof checking its condition. Next I'd be inside checking for water leaks inside closets, cabinets, behind furniture, around doors and windows. Water damage is a deal killer for me. Clean carpets are a good indicator of care.