Waterfowling can get extremely expensive. I'd recommend looking into used decoys and then look up videos on how to flock and paint them. If you're handy, you could get really nice looking decoys this way for much less than new. I'd also try hooking up with a good friend or two and try going in on a spread. There is the obvious drawback of co-owning decoys if there is a falling out between you but, it could double the size of your spread. I don't know too many guys that field hunt geese alone anyway. So try hooking up with like minded friends and see what they have, then go out and try to buy something to add to the spread. Each year add a little to it. In a few years you should have something decent.
Marcus99 is spot on. Our spread includes a mixture of full bodies, shells, and silos. Also right on with being where geese want to be. Sometimes it takes only a dozen or so decoys if you are exactly where the geese want in. Your hide is then most important.
to warm barrels and cold noses