First off Never sacrafice Price over your Life. Most all of My Treestands are made of Pressure Treated wood. I use 2X6's for the Main Frame and Decking for the Platforms, with 2X4's for the Support Rails, and 2X4's for the Steps. Sorry no pics but there Not Cheap, most cost around $50+ to build and I also Use Spiral Nails so they dont Pull out of the tree. But every year I check them thouroughly and add nails as Wind will losen the Nails.
My Wife and I can Hunt in them togeather and I can even take a Nap with Plenty of room. I feel much safer in my homemade ones then one rated for 250lbs. But again you have to have the right trees to build one and there IS a Place for a Potable where them Sneaky Bucks never go near a manmade one.

One of those portable huts would be nice, but I don't think it would do any good where I hunt unless you can figure out how to get it in a tree. I may look at some of the home improvement stores around here. A lot of them have cull lumber that's pretty cheap. Some of it is junk but some of it is leftover after somebody wanted a foot or two. Either way, I have a little bit of time before I have to have it done.