Another thing they bought was a Rare Astronomical Database, which they decided meant it listed several secret jump routes, I gave them 1d6 and they rolled five, which they proceeded to put on the star map. So their station, with a shipyard and not much else, has a direct cross-border jump route to Vool'k space.
Their HQ is not the station. Their HQ is their ship, the Mad Prince, registered as a merchanter out of their station, but actually a 600 ton hunter ship, crammed with guns - no lasers in this setting - and missile launchers, armored, and with powerful drives, both real space and jump vanes.
They also bought a bunch of Bolt Holes - tiny emergency stations hidden inside asteroids - some spy rings on the major stations in Tamberlin Space, a couple of mid-level agents, one double agent ostensibly working the other side, and station security and some mercenaries (pirates) to board captured ships.
The initial seed money for the Association came from the exiled monarch's secret stash of hidden resources, who they decided currently resides in exile at the Central Station - outside Tamberlin Space, technically, but controlled by the Tamberlin. It is currently financed by sale of the cargoes they loot from sympathizers of the current regime, and sale to aliens of the ships they take, the shipyard acting as a chop shop.
The leader of the player characters is the prince in exile - the Mad Prince - a PC who volunteered for the job. Yay! He makes all the decisions for the PCs! I don't have to! :D