I use the cardboard bales, about 4' by 3'. I have four of them in the lower lot. They have been there for years, summer and winter. Have had untold numbers of arrows shot into them. I face them with laminated refrigerator boxes and draw my targets on them. Generally only have to replace that part annually. The bale butts offer four sides upon which to place targets. They are large enough for life size deer or antelope. Caution heavy enough to put a wow in your tailgate when loading. Check the big stores. They may charge for them now, but they can last an easy 10 years. Set them on pallets or truck tires, not bare ground.