Its welded frame 2x2 11ga square tubing we placed 11ga 5in straps in the middle, inner is 2 sheets 4x8 plywood and a 4x8 3/4inrubber mat. Then welded the 18in pipe along the edge to hold the bands....
thinking that's my route as well I have a buddy who is talking about driving to there place to pick up some gear might have to ride along they give a pretty good discount if you pick up.
I figure he was looking to sell not get raped or Maybe his wife wants it gone like mine and you just list it high so it wont sell but you can say your trying.
I like the 1/2 pound idea but cant see justifying the price. I also know how much harder it is for a single guy to compete with the mass producted items. Good luck and I like the square look.