It's hard to say. I say stick with your gut. Also if you are being offered a Hassy with a back and a lens and are worried that it's not going to ever show up then sell the rest of your gear. If it shows up ready to shoot then great. If not then you got some money that you needed anyways from your old gear. If you think this person is going to send it then hold on to yur stuff for say 30 days. If no camera shows up then so be it and sell your gear. From your posts it sounds like you have fallen on hard times and may need the money more then a worring if you're going to be given a camera. Also like Zsas said if you have another camera then go shoot it regardless of format.
And people do give out Hassys I know because someone unknown to me sent me a 500ELX, two backs, and 5 rolls of film last month.