We are thinking of establishing our residency in Montana. I've tried to do some research on the internet, and most sites state requirements for college entrance. On one site, it stated that you could establish residency after 120 days, so I am a bit confused. Also, on one site, it said there was state tax on new vehicle purchases, but did not say anything about sales tax on existing vehicles brought to the state. Can anyone clear this up for me? Thanks!