Originally Posted by SBB2016
My understanding is that the school uses the residency you select at the time of the AMCAS/AACOMAS application. I am NOT eligible for CO tuition rates...
This does indeed get quite complicated quite quickly. Remember, the admissions office staff are there (in part) to answer questions just like this. I wouldn't hesitate to contact them and ask what they want you to do. I'd imagine it's a pretty common question.
From a legal/technical perspective, you can claim residence in a state once you'd start accruing/owing taxes in that state. There's a difference between a *residence* and a *domicile*. Think of your residence as the place where you currently reside. Your domicile is your home base. Your residence and your domicile may, in fact, be the same place. But they might not. Example: you're a college student in Virginia, but your parents live in/you group up in Florida. You're a Virginia resident, with a domicile in Florida.
To address this issue and to prevent "cherry picking," many/most states have a clause that you must be a legal resident of the state in question for at least one year before you can qualify for in-state tuition. But anyone who handles financial aid at a state university will tell you that the "test" for residency is often 12+ questions long.
Remember, for tuition purposes, you have to be a resident SOMEWHERE. Fundamentally, there cannot be a situation where you are a person "without a state." Schools cannot play themselves off of each other refusing to grant in-state tuition status for either state.
Anyhoo, relocate, get a job (doing anything!), and start paying taxes to your new state. The legal litmus test is whether you are paying taxes in that state. So get a job, transfer that drivers license and your vehicle registration, etc. The moment you do pretty much anything like that you can claim to be a resident of that state.
Sorry for the novel on the issue! I once worked with a property tax collector who would get red in the face everyday over people who lived in one state, but parked their car, boat, airplane, or whatever in another state to avoid taxes. Imagine every variation on this theme you can. People get wildly creative about avoiding property taxes. It's actually quite funny if you can avoid getting angry about it.