No easy answer or a standard fee if this is a retrofit type of situation where the wall needs to be cut and power brought from some existing source (other outlets, light fixtures, etc.). The variable is the amount of time it takes to do it depending on the logistics involved.
Best to do is to get several quotes and have them break down to material vs. labor charges (How many hours at what $/hr rate). That's the only way you can figure out if someone is being fair or not.
|