Mont,
I am one of those potential buyers who got some photos of your airplane. I am not sure why one of your reponders said that a 172 will cost several fold to insure compared with a 150: maybe he should look at EAA's Falcon Insurance which I am going through. I think you might be pleased particularly if you have time in the 172 and you are current.
I have the same concern as you: how can I take a load? That is why I am hesitating about your airplane since I cannot take my wife and daughter in it along with some bags. I am looking at several airplanes that may fit my bill. A 150 might, but I would have to leave either the baby or the wife behind. A 172 will burn more gas, but the maintenance costs will be the same and, if you only load it up to half its useful load (full fuel, you and a child), it will perform quite well.
A friend is trying to interest me in a package deal: a 1961 Beech Debonair and T-hanger purchase (not rent). Looks good to me, but I am afraid that the Debonair's operating and maintenance costs will eat my lunch. I am looking at a 172 myself.
Bottom line: Your next airplane will be your next love. Assure yourself of your buyer. If he is a good one, he will love your 150 as you have and he will take care of it and provide a good home. I would also agree to WAIT until you have your next airplane selected before you commit to selling: there is always a market for a good 150.
Steve