Bottom line: if you have the time and energy, using Hauseit is a no-brainer. You can pay yourself tens of thousands of dollars by saving commission on a broker.
If you're selling your property in NYC, you'll be doing all of the hard work anyway - cleaning and staging the property so that's ready for photography and open houses. You know the property better than anyone and can talk it up. But if you hire a broker, you're out 6% and the alignment of interests are terrible - they want a sale at any price, not at the right price for you.
With Hauseit, you can list for less than $1000. That's the listing itself, photography, and a floorplan - everything you need. Once the listing hits the MLS and StreetEasy, all the buyers' brokers see it immediately and you'll get inbound requests from brokers AND un-attached, individual buyers. If you're lucky enough to find an un-attached buyer (no buyer's broker), you pay 0% commission.
If you have the energy to handle showings and open houses on your own, you can pay yourself tens (or hundreds) of thousands of dollars for the effort. For me, it was absolutely worth it and I'd do it again in a heartbeat.
My personal experience: I had two offers within a week, no brokers involved, and saved all 6%. We had tons of inquiries from buyers' brokers, so the listing got the right exposure and didn't suffer any "FSBO stigma."