From what I understand, you can get instate tuition at CU after your first year.
Things to do right when you move to CO:
1. Register your car with CO. The cost of this will depend of the value of your car. If you're driving a new Audi expect to drop at least $700 for plates.
2. Open a bank account with a local branch, and keep that account indefinitely.
3. If possible, try to find housing that you'll be able to stay in your second year as well. I don't think this is a necessity, but I think the longer you can remain at a single residence, the better.
Lastly, make sure you're not receiving any funds whatsoever from mommy and daddy, or if you are, launder it somehow. I had a couple friends in undergrad lose their opportunity at in-state because CU found out they were still living on their parents' bill. But I'd contact CU directly for more accurate info. My input is mostly anecdotal.