How much would it be to have a locksmith make a key that worked for my car?

Okay so here's whats going on: I just bought a new car from a used car dealership. I didn't check to see if the keys locked and unlocked the vehicle (oops). The driver side door is not the door that came with the car (it had been in an accident) and the penger side door doesn't unlock either. I've been climbing through my hatchback to get my car unlocked. I don't need to have the panger door open with a key, just the driver side. How much would it be to have a key made that worked for the driver side?