Just keep looking! That one you don't want anything to do with it. There are sound, older RV's out there. Are you looking for a motor home or a trailer? I gather a motor home since you posted in this forum.
Ignor mileage. With older units it is not the mileage, but the condition that counts. You might consider a Craigs list ad for "Wanted - clean, older, sound Motor Home for $5,000 or less". You will get a number of calls for units that are trash, but you might fine a jewel that has just been sitting and will need refreshing, but not rebuilding.