Seeing if your aunt will sell you some of your uncles gear might be a good way to start. You have been given some good advice already and just to add a few ideas for you to think about. First off I would get myself a good Gortex hunting coat, something waterproof and windproof and being in Michigan make sure its warm. I wouldn't go cheap on this piece of equipment. Next I would get a good pair of warm insulated waders and buy the best you can afford and make sure they are comfortable. I found if you go cheap you end up cold and wet and that doesn't make for an enjoyable hunt with these two pieces of equipment. I wont comment on a shotgun because that is obvious and I believe you already have one. Next is decoys. A dozen to start off is not bad, but you can get approximately 3 dozen decoys in a netted decoy bag. Try and get several different species in some different positions. Some Mallards, Some Pintails, Some teal and this is just an example. If you can have a mix of feeders, and resters, and uprights or duck butts, it all adds to the authenticity of a spread and all fitting in one bag. It doesn't take much. Next I would invest in a cart. I purchased a small game cart that I load up my gear on and pull it and push it to the blind. It makes things a lot easier. One can be had on sale for about 50 bucks + or - . I put my wader bag, shooting bag, decoys, soft cooler, my stool, a back pack and my shotgun, all on the cart. I'm not 20 years old anymore and try to make it as easy and pleasant for myself. I have to walk into my hunts and I usually put on my waders and coat when I get to the blind so I don't overheat and sweat when pushing the cart. Now some good scouting to know where the ducks want to be, and some calling practice as mentioned previously and that is how I would start. After doing it a few years you will accumulate gear and experience and spread out the expense over time and the hunting will only get better for you. Hope this helps.
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