I don't know what demographic you may be looking for when it comes to the framing business, but if you are likely to get more mainstream clients or are looking for more mainstream *art collector* type clients (They are the ones with the money) I would look for a place that is a little more mainstream. They would likely be put off by the decor and unless they are already established clients may change their mind just seeing the place.

The place you describe, seems like it is more geared toward the goth and grunge crowd and they tend to not have the money to get posters or art framed. If they want stuff framed they are likely to just go buy a poster frame from Target and do it themselves.

Then if you are thinking about using the space as living quarters, there is the noise issue. And the access issue, who will be hanging out in the hallways outside your living space? How secure is that space going to be? Will they be smoking? and what?

Have you looking into store fronts with attached apartments? Something that you might be able to make the front half of the shop the frame shop, open to the public, easily accessible from the street and visible, and the back section the studio. The space could be easily divided with a wall or temporary movable folding screens for when you want to open up the space for exhibitions or something.

Things to think about.