has brand new tires
Do they just
look new or have you checked the date codes? If they are over six or seven years old you may have to replace them anyway.
just use it through the summer and buy a new camper.
Check trailers for sale of this age and type in your area, I think you will find they go for free or as high as 2K if in perfect condition.
You might be better off to take the money you would be using to fix this trailer up and buy the new camper now. I doubt you will get your money back when you go to sell this trailer and you will have many man hours into it also.
I restored an old Class C once and I would not do it again.
Good luck