Hi, there!
BB-2 doesn't do that sort of thing. One of the many ways it's an annoying 'droid.
When you are able to go to the Pirate Base you meet the contact your crew has. He will want a favour done, before he lets you do business. Do the favour, come back, and he will tell you you're in, and he recommends someone as an engineer. They turn up while he's talking. Just click on the new person and see what they cost!
Enjoy your new crew member!