I think there's an awful lot of potential repairs/replacements for that price. The pristine shell is to be desired (the clearcoat/exterior polish is the last thing I'd worry about, considering the structural/habitability issues you're probably facing) but some on the forum might disagree with that.
Having replaced the rear floor in both a rear bath ('72 Overlander) and rear bedroom ('73 Sovereign), I can say that while the rear bath rots out more often, the rear bedroom can be just as bad, if not worse. (Mine sure was.) Once the rear seal at the beltline/trunk lid fails, you're going to rot the plywood and rust the frame. My rear bed Sovereign's last crossmember had disintegrated by at least 50%.
If the floor is noticeably soft up front, I'd suspect frame rust and I'd be real careful of where the A-frame meets the shell. Mine is rusted pretty bad on the Sovereign
(haven't gotten to the front half yet, other than to remove the banana wrap and bellypan forward of the axles. A friend (another forum member who shall remain nameless) just recounted his experience with an older unit on the road in which he nearly lost the coach when the A-frame "cracked" and bent at that point when hitting a dip at highway speed.
What I'm trying to convey is that with aluminum skin surrounding everything, it's kind of hard to adequately assess condition of the unit. I'd toss the furnace, plan on replacing most if not all appliances (nearly 30 year old appliances are not very reliable unless lovingly and carefully maintained...not likely in this case).
He probably won't take less than $6K because he knows there's another guy right behind you who's already purchased the polish and rented the polisher. (Okay, maybe he's just been pricing the polish.) And $6K might not be a bad deal if you don't mind spending another $3K-$6K to get it like you want it (not counting the hours of "therapy" you'll receive while drilling out rivets, scraping off old vulkem and silicon, etc.). It's just a good idea to know what you're getting into beforehand. Expect the worst and you'll never be disappointed!
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