I almost got to play in a Starship Repo Man campaign, but we spent the first few sessions just investigating/skiptracing, then the group fell apart for unrelated reasons. So no experience, but we did a little bit of brainstorming.
The obvious weak point is at starport. As kokopelli says above, at a high enough law level you might just serve notice with starport security backing you up. But in many places you'll need to be prepared to board and take possession first, present your credentials second. Computers, Mechanic and Stealth would all be useful for getting through the hatch and to the control room, ideally while the crew is on shore leave.
If that seems unlikely you'll have to get creative. Tempt the crew on board with alcohol, women, gambling, addictive VR chips, whatever it takes to get them out of position or just out of shape. Ship a cargo container full of your own guys, just to get them on board. If they're still taking passengers, book every ticket with your guys and rush them once everyone's on board. Fake an emergency at port, but do so before they've refueled so the crew move. (The last is better if you can spoof only the ship, faking an emergency for a whole starport is likely to be a Very Bad Thing.)
If you must go ship to ship, call on the bank or megacorp for back up if there's any in system, or just hire on a couple more freelancers and accept you're splitting the fee more ways. 3v1 is a lot more intimidating than 1v1, and can hopefully wrap up faster with less damage if they do fight it out.
Or conversely, boarding actions don't have to take a starship if you can locate the target inbound and hit it outbound. Could be a bunch of belters and mercs in suits on rocket sleds, launched from a civilian model M-drive only spaceship. Low profile, not apparently threatening if they're encountered near a starport or jump limit until they launch the suits. And while those will be obvious if someone is actively manning Sensors they won't necessarily trigger any automatic alarms, the energy and mass is low until they're close.
Or if you're very high tech and you have the bank's access codes, you could just attempt the infamous "I hack the ship" Computer roll. I don't actually like this one, I can't imagine people wouldn't just air-gap their ships' computers, but maybe if you're still paying off the mortgage they leave a backdoor for just such occasions.