In the Cartel Market on Fleet you can buy a contract from a little Robot for 1 Million Credits that will lead to a quest that will eventually unlock Treek, a new companion.
What kind of companion is he and does he offer any quests that can be played, like e.g. Vette that has some nice quests? Does hiring him raise my limit for sending companions on Crewskill Missions?
(HK-51 didn't, but HK-51 is essentially free).