Water damage

If you buy it I would do a complete re-putty on it in order to keep it dry for years to come. No matter what's going on up there it's time because the putty tape dries out after that amount of time so even though you see no damage on the inside yet, it doesn't mean water is not getting in above that now. By the time you see the damage from the inside it's too late.

Welcome to the forum.

Thanks for the advice. I don’t think there is anything serious going on underneath, as the walls are solid, and the areas around the windows feel pretty good, and the interior does not have a musty smell. I will re putty around the windows, door, and power hookup to be safe. Are there any other things I should be looking out for?

It sure looks nice on the inside. Danny

Larry, he said his grandfather built it on a old chassis, I'm sure he took some liberties with a home built. Danny

Even though it's home-built, I am betting that it was templated from what was already there, and perhaps some of the building techniques were copied to put it together. It's a pretty good-looking ole trailer in my opinion. I'm sure we'd all agree that we've seen plenty of them that looked similar from the outside.
Take it to task with the icepick test first, that will probably show up the most likely indication of any hidden suspected rot. Check the bottom of the skirt boards from underneath for soft and punky wood and especially in the corners at the front and rear corners. If no signs of any rot there,then you may not be in for any unpleasant surprises.

In any case, home-built or not, it is subject to the laws of physics that govern old trailers.
First, "Sh&t runs downhill", so the first place water damage will show up is at the bottom. Second, "Putty tape will absolutely harden and shrink over time", so all the seams will need resealing, if it hasn't been done in the last few years. You definitely seem to be starting off on the right track with this one. Best wishes as you explore!

I'm just going to hang back and watch on this one. The lack of supporting cabinets is a threat to the structural integrity but without seeing the entire trailer and not knowing whether it was a frame off or not I can't come to any conclusions. I've got a clear chassis out back and I've been considering building a custom canned ham in the future. It will have all the usual cabinets in all the usual places. When we stray from common, time proven theory it's a little scary so I'll be sticking with the norm. 

I totally agree to do all the test that have been advised.

Having family history can be a strong connection and that can be like looking at it through the proverbial rose colored glasses.

Anything can be fixed but there is also a price tag attached to vintage camper that is structurally compromised, The members here really want to help new members avoid the pitfalls of buying that dream camper and then realizing the dream has turned into a nightmare.

Good luck. Danny