Just use plain old spray paint in a can. I've done it many many times and seems to stick really nice. Nothing special either I can't even tell you the brand because I have no clue. But as mentioned doing 2-3 light coats helps.
no expert here, but heat doesn't rise. heat radiates in the direction of least resistance (R value).
warm air or water rises because it is less dense than colder air or water. If you don't insulate you will be heating the ground under your cabin and the earth is a very large heat sink $$$. get some info from an expert in the radiant field as far as tube diameter, spacing, water temp, manifolds, length of runs, and so on. it varies on amount of windows (solar) ceiling height and room type (bed, bath, living area, storage etc.). once you pour over the tubing you get to live with it. I did my own Home 15 years ago and got some good advise (wish I would have taken it all)
You'll probably run into plenty of "experts" among the experts, too...
Floor heat is nice, but definitely not the best option if you're looking for the best efficiency, since it is a slow recovery system. If you were looking for efficiency and lowest cost, I would suggest looking into a mini-split heat pump to complement the gas furnace if you have off-peak available.
(Disclaimer: Not an expert either, but I have stayed at a Holiday Inn Express a few times.)
Same here. I have 3 of them. Use them in the SUV, Boat, Snowmobile, and Dual Sport bike. They seem to work better on my sled in the winter with no issues at all over my old ifinder which would eat batteries in the cold. They are discontinued but you can still find them out there on the List or bay once in a while. I like them as they are a crossover and can be used on the road or with a lake map which is the main thing I use them for. Wish they would bring something like it back.