We've had TCs for the last 30+ years. The last one is a '89 Dodge Cummins that we bought in '93. It now has 286k miles on it and I would not hesitate to take it anywhere.
Like others here, I do my own maintenance and keep records. If I didn't I wouldn't know what I did last to any of our 5 cars, TC, MH, 5 motorbikes, or the boats. When it was just one or two I could remember, but not now. I think records are good.
Now we have a "new to us" '93 Flair 26' MH with only 40k miles on it and we're planning a 8k mile trip with it this summer. I knew it had a few things wrong with it when we bought it, but shorter class A MHs seem difficult to find in fairly good condition. We also liked the floor plan and the interior was good. We paid $7500.00 for the MH and traveled 900 miles to get it with the Metro. We towed the Metro back with the MH.
At this point I've replaced the radiator, water pump, belts, hoses, AC compressor, converted to R134a refrigerant, and the coach batteries. I'm also working on many small leaks, replacing the refrigerator cooling unit, and plan to replace the brake master cyl. and hydroboost unit, possibly the rear brakes, and at least four tires. The tires have lots of tread but are weather cracked. I will also replace the outer skylight over the shower and install a better shower enclosure. The awning will also need some attention where the sun has damaged it at the top by the roller. Of course all lubricants will be changed, the chassis greased, and the front end has been aligned. I also have a backup camera to install so we can watch the toad. At this point I think it will be ready for the summer trip.
When we get back, if we still like it, I will probably replace the rubber roof along with a few other things. At that point we will probably keep it for many years.
This is the difference between a well maintained camper and one that was not well maintained. The list of things I am repairing/replacing on our "new" MH can also be used as a partial checklist when looking at your prospective purchases. I'm thinking I will have at least $3000.00 in parts, with no labor cost except the alignment.
Best of luck with your purchase.