Apparition,
Congrats on the interview. My interview was first thing in the morning (8:30 or 9) and the whole day was done for me at approx 2:15. If you need to catch a train you can cut out of the tour early, it won't be a problem at all (other than you missing part of the tour, but they don't show you anything spectacular).
As far as resident status, you are probably out of luck. Most schools in VA require that you be a resident (voter, live here, pay taxes, driver's licence, etc) for one year prior to enrollment in school. So, unless you already live here, you are probably stuck with out of state tution your whole time here . . . sorry (someone might know more about this than I, but I'm pretty sure that's how it is, you can certainly ask during your interview).
Good luck. If you have any questions about MCV, I have 2 friends there now and am willing to pass on whatever aid I can.
Edit: Don't know anything about student hosts . . . I live too close, didn't need a place to stay.