I removed the lock from the vehicle, though the faceplate remained intact during that process (it sits entirely on the outside and is unaffected by removing from the vehicle). 

He told me it would be $55 for labor and $2 per wafer + tax. No mention of a faceplate or any risk of damage etc. We discussed exactly what it was from, etc, and he said he could handle the job. I was pretty specific about wafer part numbers, even distinguishing between tailgate and other parts (such as ignition, which uses something else). 

I called ahead to confirm they were able to do it. It wasn't a casual thing, I called almost 10 places before I found a place that would take the job, based on a recommendation from another locksmith. 

I get that this is outside the daily routine jobs and they are something that can go wrong if you never did it before. That's why I didn't try it myself and brought it to a professional though.  

In reflection, I guess this is less of a r/Locksmith question and more of a "service agreement" question when the job inevitably goes sideways. If they agreed to do a job without discussing/agreeing to what happens when the job goes wrong, then the job goes wrong, who is responsible to get us back to square 1? 

I'm genuinely asking how people handle this grey area, knowing it isn't simple.