Years ago my father purchased a large piece of wood. I think it was 8 feet by 8 feet. I had him trim it, but wish I had left it whole. It is 6' x 4'. He covered it with adhesive shelf liner. I lay that on the dining room table. I use inexpensive clips I purchased from Home Depot. There were 25 cents each - probably a little more now. They open wide enough to clamp the layers to the board and have plastic tips so they don't bite into the fabric. If the quilt is bigger than the board, I clip half and attaché all three layers with basting spray or pins, then unclip, move it up and do the remainder of the quilt.
Home Depot does not charge to cut wood to the size you want. They say only cut one piece out of each board, but I have had nice employees cut two pieces. Take all the left over pieces, you may come up with a use for them later.
I can slide the large board behind the furniture when not in use.