My mom just bought one from my cousins girlfriend $50, From what I can gather it is a Korean made Martain D-18 copy.
This isn't the exact guitar she got but this is what it looks like:
I guess it is also a '70's made acoustic.
Good deal for $50 bucks? Yes or no?
Basically any guitar that's half way playable is a good deal for $50, IMHO. If you don't immediately want to throw it in the garbage, it's worth $50.