I'm usually pretty good with SEARCH here for finding stuff. Know someone had mentioned scissor jacks before but can't find it. Troy has couple photos recently listed with shots of one (stole one and posted below). I'm building 34x40' barn and like the recess shown in Troy's. Need to figure how large to make it before the concrete is poured - and how thick concrete should be around the indent. Think I once found the lift on Harbor Freight for under $2k.