Do it all in the garage. Dad always used a oiled sheet of plywood growing up in ND. A couple years ago I started using food grade HDPE plastic. Found a plastics factory in Washington state that sold me a 4x8 sheet of plastic for $20. Stationed in Omaha I paid $50 for a 4x8 sheet probably 1/8" thick, had them cut it in 4 two foot sheets for storage. Just throw it on the plywood for a large plastic cutting board.
Need to find a plastics factory in Colorado to get new sheet, let me know if you know of any.