Relocating light switch

I am working on a new barn and I'm getting to the point to consider my power options. Originally I thought I would just install a new meter/service on the building due to the incoming power layout from the utility. It would be less wire and overall easier I figured than running from the house. Problem #1, when I called the utility they informed me my minimum bill would be $50 a month for a new service since its not a residence. So my next option is from the house. I have a 200 amp main where the meter comes into the main panel. The main panel also feeds a sub panel in another part of the house from a 100 amp breaker. On top of that the panel is full. So what I would like to do is install a new panel that is fed from the meter base so the meter base would be feeding 2 panels. From there I would trench the wire to the barn. Has anyone done this sort of installation before? I talked to the utility and I think that there is sufficient wire size from the transformer to the meter to give me 350 amps of service though I still want to confirm that 100%. I would probably run 150 amps to the barn in that case. From the house to the barn would be about 250' of wire I estimate. Any thoughts, comments, or suggestions?

Ok so I am not looking to die today due to electrocution. So nothing out the ordinary has been plugged into any receptacles in the whole house. No thunderstorms or obscure amouts of rain. No power outages in the neighborhood or in my house. I was sitting in my living room, in the evening, watching t.v. all of a sudden all the lights in the house went out. All of the outlets still work and nothing in the breaker box was tripped. In about 1 hr the lights turned back on. 2 days later about 10:00 in the morning it did it again for about 3 hrs. Then the lights came back on. I checked every gfi in the house and the only one tripped was the one in the bathroom. When I reset it nothing happened. I assumed it was a bad gfi and changed it out with a new one. It is a gfi with a light switch attached to it. I thought I fixed the problem but the next morning (today) around 7:00 in the morning the lights went out again. I checked the breaker box all is good. I reset all other gfis and all was good. I tried to reset the new gfi in the bathroom and it wont reset. It has been 7 hrs now and the gfi is till tripped and the lights are still off. I did all the troubleshooting I'm capable of and am now at a loss. Please any help with this would be very much appreciated.