Thank you everyone for your answers! Since I am looking for a cheap option and something that I can build (I think that it would be a fun project) I still plan to carry through with my p&s plan. However, I am going to look for a wider lens (45-55mm ideally) as wells as not use a helical mount (too expensive). What are people's opinions on using a two box design (with one box sliding inside of the other to focus) vs. a plain old box?