The site's UI is pretty smooth, with some very minor bugs (at the moment you can't add blank lines to the house description textbox). For an MVP it's very very clean and a pleasure to use. There's an unobtrusive "Seller tips" box that has a fantastic checklist for prepping the house. I mean, I knew to replace the tile counter with marble but I never thought about replacing the doors' weather stripping.
In the too-good-to-be-true dept: chatted with the founder and this appears to be a legit deal. Certainly they haven't charged any money, and he obviously knows the applicable laws: he's been in every possible position from developer to broker and everything else. In lieu of a big market spend he's just going to lose money on every sale early on. It really does cost only a buck to sell, and they do plan to send a distinct for sale sign. I suggested he make images of that sign prominent b/c the site is a little generic and that will set them apart.