I would suggest using the website I linked for you to study up on the models so you will be more informed when you finally see one locally. They are all pretty good, some have plastic lenses and some glass, it depends what you are looking for. No matter what model, make sure the battery compartment is clean. I'm not much of a fan of Impossible film but I know they are getting better, so for right now, I prefer the peel apart Polaroids, so the best ones are from the mid 1960s to the mid 1970s.

Chris