I grew up duck hunting on the marshes & farm fields in NW Ohio. My son now hunts duck, geese, and deer. The cost issue is what you make it, how many decoys do you need, more is better. If hunting water then a boat/motor painted camo will be needed. Never hunt solo when hunting water, too many things can and do go wrong. Try to find someone experienced in decoy set-up and proper calling it takes years of practice to do it well. Shotgun 12 ga, at least 3", many are going to 3.5" for geese. Small streams can be hunted from a canoe and a few decoys say 1 doz. Big water hunting and 6 doz decoys would be needed and a good boat. I don't think duck hunting or anything else would replace deer hunting but too many sports may replace the other half and that might be a bad thing.