Plenty of weekly moorings available to leave the boat for a week. I'd jump on Concord as Max mentions. There's almost no limit to what you can haul along in the cargo hold and it's not a bad ride to Portsmouth, plus it's dirt cheap, comfortable(wifi) and the terminal is just about it all the dinghy docks in Rockland.

Rental cars are plentiful too and they'll drop most anywhere. I hope to meet you when you're up here(and maybe Max too!)