Might not be a bad idea. For such a niche item I would say that you could locate your business pretty far outside the city (to drive down rent/real estate costs) and still have a plethora of people willing to make the drive to your store. Simply because there is somewhat of a shortage of classic bapes/nikes/bbc/etc. that are not sold in stores anymore, i believe you could draw quite the crowd. As far as legality goes - It is not illegal to resell used clothes of any brand. Obviously you cant make flyers or signs with the brands names on them, but an advertisement like "designer urbanwear" or something like that would certainly get the point across. If the profit margins are high enough, I'd say go for it. Most of your costs are pretty much liquid too. Assuming you don't get enough business, the real estate and clothing should sell itself on the internet if you are forced to close (Assuming you purchase the land instead of renting).
Just my $.02 , I'm sure there are apposing views out there, just thought the thread was interesting cus im in the process of raising capital for my own business. Whats your sn on PStars? Ever play Absolute?