C172
I would go with the 172 anyday. With the limited useful load of a 150/152, you may have to turn some of prospective students down due to weight issues. If you go with the 172, you would also have a sturdy IFR training platform and could offer instrument instruction as well. All in all, just a whole lot more utility for the $$$.
But, of course, this advice is worth exactly what you paid for it . .
Regards,
FlyWest