Hi Frank.
Welcome to the club...and congratulations on contemplating your first aircraft purchase.
I agree with my esteemed colleague, Wayne. Regarding engine times....you generally get what you pay for...but that is by no means an absolute.
If you prefer the electric flaps, then that's your preference...just like your favorite color is your favorite color....and it's not a wrong decision. However.... I'm one who has flown a lot behind both electric and manual flaps....and I have to say I absolutely love the manual flaps.
The motor never fails me. I learned that the flap motor does get tired with repeated touch and goes...and the flap motor works harder closer to the max flap airspeed...but the motor never completely quits. It's a simple, very reliable system...further keeping prices down.
But, that would limit you to the '59-'65 model 150's. I just wanted to throw that out at you. I wish you the best of luck with your search and ultimately in your purchase. What an awesome feeling...to fly your very own plane....with no time limits on when you've gotta get it back to the FBO.
Again...welcome to the club.
