I just want to add my 2 cents. I can't help you with the price or opinion on a 5th wheel.
We have a 96 Southwind and are planning to buy something newer.
My wife likes a motorhome and would not be happy in a towed unit.
I like the convenience of a motorhome, everything is available while traveling. No need to stop for her to get something from the fridge or use the toilet.
Maybe trading to a smaller gas Class A or Class C would be an option?
Yes, you still have the engine/driveline to maintain.
But, is your wife willing to give up the convenience?
Especially when you pull into a CG at night when it's raining or you're just tired. Level it and go to bed.
In a 5th wheel or TT you must leave your tow vehicle to get into the RV.
We'll stick with a Class A or C just for the convenience. And, we don't use ours as often as we want to, but it's worth it for us.
JMO.
Good luck with whatever you decide.