We must remember too where Tim lives. Although this summer has been very dry, typically Portland is a very drizzly climate, especially through winter.
I choose to hangar, but I can also see why one would not. However, Tim, if you DON'T hangar, I would recommend that you consider getting some good covers (the ones that go over both the windscreen and the wingroot areas, or the mold and mildew from a leaking old airplane will drive you nuts in short order.
There is a club member who I know has a 150 at TTD and his is outside for the same reason you cite.
They won't melt away, for sure, and your biggest enemy will be the rain, and sun damage to the interior. A good cover for a few hundred bucks (which may have to be replaced every few years) may remedy that to the point where there is not benefit.
Quite frankly, at $1500/yr, I have reasonable rent, plus I would otherwise have to rent some storage space, so it works for me. If I had a fabric plane, I would not leave it outside, but a 150 or 152....well...it's an economic vs. preference choice really.
