I'm sorry did somebody say a C152 is worth nothing? Gee there must be a lot of people out there wasting there money on advertising 152's for up to 60k!
Sure Cessna doesn't make them anymore but they also didn't start making any RG aircraft either and are they worth nothing?
Heat, I would suggest that you go and chat to some people have an idea of ACTUAL costs not somebodys guess.
At the right school a 150 or 152 should plenty of hours but if a school owns one 150 and has another that is cross hired guess which one will do the most hours?
Buy an aeroplane if you want one, but buy shares in BHP if you want to make money.