Group wants to find a NPC mechanic to fix crits to ship.

Allowable? Negotiation to find the mechanic I assume, but how many dice does the mechanic use to roll to fix it? Does he even roll? What's the cost for such a thing?

If a hull point is 500cr (average) to fix, then a critical component is probably going to be more expensive. Maybe 1000cr per difficulty die as a baseline?

I'd definitely make the mechanic roll (there are NPC mechanics in the adversary decks, I think they have a YYG dice pool). Or they could hire Ugnaught minions with the Mechanics skill...more Ugnaughts means a better pool, but they'll be more expensive so...

Before the mechanic rolls, the PCs would Negotiate a good deal using the baseline values.

A trained mechanic should be able to fix it automatically, but you would have to pay him significantly.

Yeah, if an NPC is doing it I'd say just give him the cash and it gets fixed automatically in whatever timespan suits the adventure.

If they want a cheap job they could hire someones workshop after hours to try and fix it themselves (2 Boosts to check, 200 x Silhouette x Crit Rating or 5 Group Obligation)

If they pay a bit more the Mechanic assists them (2 Boosts + 1 Upgrade, 500 x Silhouette x Crit Rating or 10 Group Obligation)

Or they just pay the mechanic to fix it (No one rolls, 1000 x Silhouette x Crit Rating or 15 Group Obligation)

Edit:

Negotiations could change the price, perhaps 5% per success or 2 advantage. Triumph could be used to gain info or a tempory systems boost for their next encounter.

The mechanic doesn't need to make a check. I'd also say that a PC shouldn't need to make a check if they have access to appropriate facilities and enough time to do the job (which may not always be the case, of course). Negotiation would cut the price and/or provide some other benefit - but also runs the risk of complicating the situation if it goes badly. There's narrative potential there, which makes it worthwhile. "Roll roll roll until you get enough successes to remove the damage" isn't.

If they don't have a mechanic in the group but really need one I would probably introduce a NPC the players can persuade to stay with them (for some time at least).

I would probably make an adventure of it, the players rescuing a well known mechanic from some prison/ slavery situation. He could be a very special individual with some unlikely habits and a rich background (he is in prison/ slavery for some reason!) that could even be the seed for future adventures!

I would not let him do repairs for free however, because they will still need spare parts/ materials and proper facilities for the repairs.

I'd have them make the Mechanics checks just for fun though.

If they bungled the repairs it could cause a problem you could bring up in a future adventure for laughs, or even something serious like the hyperdrive overloaded by a surge in a faulty power coupling. Then they have to land to get it fixed in a conveniently nearby deserted space station... that locks the bay doors as soon as they land... so they have to find the control room... meanwhile ZOMBIE droids begin to activate!

Just a quick suggestion... what if the mechanic they find doesn't want money for the repairs, but instead a favor?

As a GM, you could use this as an opportunity to introduce something more interesting than just exchanging credits.

What if the “mechanic” is a droid, and what he wants in return for his work is access to spare droid parts, so that he can upgrade himself?

What if that droid was also a secret supporter of the Droid Rights movement, and took it upon himself to repair (and convert) any damaged droids that are found along the way, so that he slowly amasses his own droid army?

I can think of lots of interesting ways you can twist this one.