Gert Station

Found fairly near Starbase 308, Gert Station is in some ways its dark twin. Except they don't look at all alike, and a lot of the Starfleet officers who go to the starbase would never be caught dead here. (That is a lie. Even Starfleet officers know a good black market deal when they see one.)
Gert Station is a well-known hub for the sale of artifacts. The general idea is that they are illegally obtained in some way, although this would never be formally admitted in public.
A past owner was named Gert, although the current owner is a woman named Desree Kozur, a Joined Trill. She runs a cautious station, strict about who finds out the exact location, and precise about how people are brought onboard for auctions and sales. She's also careful about what gets brought on board. Nothing specifically dangerous or with known side effects. Only artifacts, no weapons.
The station itself is cleverly constructed to look like an asteroid. Unfortunately, it has since been moved from the asteroid field where it was originally supposed to hide. Something to do with Klingon trouble. Security systems on and around the base are extensive.
The station is infamous as a black market source of artifacts. People from all over the quadrant will come to buy and sell rare treasures here.
In order to get anywhere near the station, you have to get a letter of introduction from someone who's already been there, so that only those in the know can get on it. The price of admission is food or water or some other form of basic supply. Sure, they can replicate stuff, but those on the station don't get a lot of fresh stuff, and you can't exactly use the more expensive things for basic needs. So it's considered polite to bring supplies for the workers on the station.

Type

Starbase