The area around the eastern end of the Kurfürstendamm is still very much a shopping zone. You will basically find everything from very expensive stores to medium priced. Nothing really cheap but then the quality of the wares usually fits the price…
Also in that area is the KaDeWe which is a warehouse comparable to Harrod’s in London. However, it is quite pricy.

If you want a somewhat cheaper variation of normal stores I suppose you could go to the Schlossstraße, it’s where the citizens from that area go. Haven’t been there in ages, but the stores can’t be all closed :P It should be less touristic than Kurfürstendamm.

If you are into flea market both for normal stuff and for arts, there are quite a few, but I would recommend to check a travel guide for schedules and locations. Because my memory sucks :D

If you are more into the “alternative” type of shopping you should go to Mitte, “Hackesche Märkte”, "Oranienburger Straße" and so on. There are quite a few small shops, which for example design their own shoes and so on. Haven’t bought anything there myself, but well worth a look. In the area are also lots of art galleries mainly in the “Auguststraße” and “Tucholskystraße”. Go there on Fridays in hope of getting some free wine at a random opening ;) If you happen to enter one of the galleries in Linienstraße say “Hi” to my mom please ;)


All the German names I wrote, you should be possible to google with the addition of “berlin”. So I didn’t bother to add links myself.

/edit1
Due to popular request: Prostitutes are available in great numbers on the Oranienburger Straße, quite cheap, too for what I hear. Can't say much about diseases and or quality :P
Also several legal "Saunaclubs".