after i got my GTI, i never drove my accord, tho i still had it from january, when i got my gti, til may...when i sold it. i started up, and drove my accord around the block once a week and it was fine. the only bad thing that can come from it not moving at all, is flat spots on the tires, and the rotors getting suck together with the brake pads.....that used to happen a lot at honda when i worked there, but those cars were stored outside, so that was one thing that lead to it. since youll have the car parked inside, or so it sounds like, that shouldnt be a huge issue, but still could happen. the flat spots on the tires tho, that will happen if the car doesnt move. and sometimes, if you drive the car soon enough, you can "wear" them out. if it sits for too long....like the time of your trip....then youd have to buy 4 new tires.