How old? :). Most from the 80's will have more or less what the ones from the 2000's will have plus a few bed bugs and a lot of water damage. ;).
If you are truly handy then you should be okay. That said, water damage means walk away. You may be the most handy guy in the world but water damage will cost you big time financially 9 out of 10 times no matter how much free time you spend on it. Make sure to check the over head cab on a Class C. They are notorious leakers. I have seen new ones on dealer lots with minor leaks in them already.
Here is the only hole in your plan I see. Barring getting lucky and finding that gem, and I hope you do, you are likely gong to find most used used RV's that fall into a few categories. The first is the old beater. It's only 5 grand but it will need 20 grand worth of work and yes, your time is money. The second is the three year old rig in great shape but the seller still wants about 1 grand less than they paid for it plus an extra 2 grand for the upgrades they added. Don't waste your time on these people. I did and I regret it. They aren't living in reality. And the kicker is their units need some attention too. Usually tires just to start.
Here is another one to look for. A 10 year old rig that appears to be in perfect cosmetic shape and only has 4000 miles on it. This one could cost you big time. It means they didn't use it and it sat a lot.
Pardon my negative sounding attitude in this response. My only intention is helpng you learn from some of my own mistakes. In the end, having a hard time finding your dream rig is a darn good problem to have! :)