Denise-
Welcome to the Forums. Sorry to hear your Argosy was not what you expected.. Many members are going to be reluctant to answer your question directly (including me..
) about whather it's worth it to keep investing...
You should practice and practice using "Search" tab above, and typing in words on subjects you're interested in, and reading threads for prior messages...
Searching on Ebay will reveal that some sellers have "interesting" views of condition, not always shared with buyers. Better than outright frauds which are also common on Ebay..
Air conditioner will run about $800, tires not big deal but axle could be worse (search on "axle" and "sag" or "replace"..)
Upholstering taste and costs vary, from $ 1,000's for first class proefssional withe new foam and Amruso drapes to do-it-yourself for skilled people who sew (reads better than "sewers..")
As for floor, read about floor rot and floor replacement.. It is possible (though unpleasant to think about) that seller might have laid new vinyl over bad subfloor to make sale, and you have to fix underlying problem. Rotted plywood under vinyl won't ever "get better" by itself, and needs to be addressed...
Dents are cosmetic, unless they contribute to leaks at belt-line trim... Paint is also personal, though doing good strip job and using polyurethane paint are both good ideas.... Some try in their backyard, others go to body shops, or have a friend in the business.. Paint alone (Dupont Imron type..) is going to be several $ hundred "uninstalled"...
DON'T use silicone sealer to fix leaks, and do stop water from getting in wherever it is coming from..
As for value, in the end it comes down to your budget and plans to use it and desires.. If you love the look and floor plan and it fits your needs, people are paying much more for perfect versions of those, and you could be happy after all the fixups.. If you just thought it was "good deal" and thought maybe you could do a few simple fixes and sell it for a profit, it may not be worth the investments..