First post here, but lurking for a while. Just about to confirm order and received the following from local electrician here in NJ. "Labor, material to install a Nema 14 - 50 amp weatherproof outlet for standard electric cars would be $1,200.00. Note price includes changing four existing breakers in your panel to tandem breakers to make space for the 50 amp breaker." Would appreciated advice regarding cost and changing breakers.