I was going to build a duck boat, then I was going to go buy the beavertail boats final attack.... I really wanted a sneak boat.... Couldn't figure out what I wanted, so I grabbed my inflatable dinghy off my sailboat and a bunch of spray paint, camo-ed it up, and it looks great, plus it's really comfortable to lay out in because of the fact it's inflatable, it rolls up and can fit in the trunk of a car too, plus because the boat is deep (high sides) I disappear right into it, and with a home made flip up blind, it can't be beat
I paid 100$ for the boat, 50$ in spray paint, and threw it together with what I had laying around the garage. Not pretty, but highly functional and economical
Check craigslist, I think the boat I have is called a quicksilver 270, but I'd get the next size up, not much room with all the decoys and gear. I put a 4hp on it, and it definatley gets the job done.