Asking price may be a little high depending on going prices in your area.
Standard advice is to have a good truck mechanic and an RV service go through chassis and house box and give you written estimates for any repairs or replacements needed. Make sure that high cost things work properly, i.e. RV generator with roof AC and microwave working, furnace, converter charger and house batteries, awning, and fridge in both propane and AC modes. Tires older than 4 years old may need replacing, engine cooling system and brakes should all be checked and brake fluid flushed/replaced.