I purchase two Jet Sleds at Cal Ranch store they are about 4 feet long 20 inches wide and 12 inches deep. I slide them in the back of my truck with a lot of my stuff in them (chains, come along, axe, backpack etc.) If I kill something I use the sled to haul it out and to carry the animal home. The blood stays in the sled and I just transfer the stuff to one sled.
I think the cost was around $30 each. I took a piece of 3/4 conduit and made a handle that looks like a water ski handle. I have hauled out a whole raghorn bull in one trip with this setup. Deer drag real easy even on dry ground. I have used mine for at least 10 years now and still going strong.