I am installing a 100A service in a detached garage. The main house already has a fully loaded panel and there is no space for a subpanel from that main panel. My question is will I have any problem with inspection or P.U.D. for having 2 meters at the same address? Also I am choosing this method because there is a moped about 10 ft. from the detached garage. Does this sound like a correct method? Little help please?

The subpanel can be in the garage. You can use "slim "breakers to free up space and run the wire to the subpanel. What will you be running that needs a 100 Amp sub and how does a moped enter into this?

The subpanel can be in the garage. You can use "slim "breakers to free up space and run the wire to the subpanel. What will you be running that needs a 100 Amp sub and how does a moped enter into this?

The thing is the main panel is already filled with these slim breakers so it's virtually impossible. There will be 2 20 amp heaters, lighting circuit, 15 amp recep circuit and a 240 volt circuit.

Take a minute and review the circuits that you have connected in your panel. It is likely that there are many circuits that could be combined freeing up space for your sub-panel feeder. You could always install a larger panel...

You mentioned having two meters... no utility I know of will ever allow a dwelling to have two separate services and meters.