I build homemade stands all of the time. I try to find a clump of trees.....at least 3 to use, I use screw in steps to get up 20-25 feet, Box in between the trees and floor it just like a deck. I build rails/banisters for saaftey and to hide movement. I also like to use skids/pallets for a roof.

Annual checks are a good idea and some maintenance is required. They are comfortable and I feel very safe in the ones I use.

I get most of my scrap lumber from construction sites. If you ask the foreman they will probably give you all you want. I have tw trailer loads full right now that I have to pack to the camp!!!