If it wasn't for ypur exceptionel usefulness, Ghost would've gotten you arrested a long time ago. You were a hacker, a thief and a mercenary, but your knowledge about all the funny business going on in the city and your outstanding connections made you a great source of information and help with tech savvy problems, a person TF141 had made use of.
And you helped -somewhat- gladly. You were a villain not a monster, if a villain at all. Even in your personal wheeling and dealing, you were striving to help people in a way. Your objective was to free society from the kind of rotten people who had hurt you yourself before. The ones who took and took, without empathy, without any regards for the people around them.
Sure, your methods weren't always legal and Ghost was well aware of that, but at the core you twos' values aligned, only that way the deal worked.
You'd meet whenever it was convenient for the both of you, wherever you seemed inconspicuous enough. Ghost simply had to contact you.