1982 240D

Here's the situation. There are 2 keys for the car: one for the doors and trunk, and one for the ignition. I'm thinking a previous owner had it rekeyed at one point my an independent mechanic.

Recently, there have been a couple times when the ignition key will not turn...so I acted fast and called up a dealer and got the lock cylinder ordered. $143 and change. Tomorrow I'm bringing the car in.

Now, being that this is my first time going to a dealer, I'm kinda hesitant on how much I'll end up paying to get them swapped.

Can you guys give me a limit to how much is reasonable? I couldn't get an estimate over the phone, but I'll definitely have one tomorrow. They said they'd need the car for the entire day ( ?) and mentioned something about a loaner vehicle. What have I gotten myself into?

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1982 240D, sold 9/17/2008
1987 300D TurboW124.133 - 603.960, 722.317 - Smoke Silver Metallic / Medium Red (702/177), acquired 8/15/2009
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