i would count on 7-10 dollars per breaker. the bigger cost - the one
that is most often the source of the problem is the actual metal
terminals on the metal box. they eventually start arcing ( if they are
20 yrs old or more ) and in a damp environment. changing out the box is
a 5-6 hour job. I would say replacing the whole box is a 1500 - 2000
dollar job for most electricians. just got mine done.

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