Burb- you sound like a "go-getter" who is handy with construction skills... and like all of us, are looking for a bargain. As others have stated, this camper is perhaps beyond resurrection. But if you insist on getting it, i would recommend that you consider it a total loss as you begin the journey and from there determine if anything can be saved.
perhaps you use it as a learning tool and provide free disposal for the person getting rid of it. You could do a deconstruction project and perhaps salvage components to sell if they are is acceptable shape, you could use it as a learning tool.
In my opinion, the evidence is that it is too far gone and there are many unknowns still lurking. You might spent time and money to then only discover something that will make it unusable. I have done significant repairs to a past camper and from what I learned was that I will never do it again. I would rather be camping instead of repairing the camper.