After I ask the question I thought about using vinyl siding for the walls, if I use the 16 in tiles and some lumber, say 2x4s to strengthen the siding and set the siding attached to the 2x4s on the tiles, I will still have at least 12 inches of tile inside the enclosure, I will be able to caulk (glue) the vinyl siding to the tiles, so they can't move. I set bird baths, large flower pots, etc on tiles in the yard and after they set for awhile they are hard to move and get up. -I think it may work-
2.Another suggestion is pounding in 12" rebar down every 4" or so. This is an alternative to digging a deep trench and lining it with concrete or wire. This is a bit easier to do before you have walls, but I have managed.
