Grand Theft Auto III/Her Lover

Brief
It turns out Marty's wife was having an affair with someone he owes money to, so it's time for another chat.

Walkthrough
Take the Stallion and pick up Carl, then drive him to the factory. Marty is waiting outside. He tells Carl he doesn't have the money but wants him to step into his office to discuss it, but Carl uses his own bargaining tool, a shotgun, and takes over the business. You can kill Carl for the shotgun ammo if you wish, it won't matter.