You make some critical points.  Colorado's special districts and enumerable tax rules and rates are impossible to resolve, especially for people outside the state.  They also fail to address the many people who own a home in the state, but are not residents of the state.  States like to treat their residents as a form of "property", trying to extend their control, and taxes, over those people even when they are not in the state.  This is irrational.  Are the taxes owed based on residency or based upon physical location at the time?  Resolving such fundamental issues should be central to any solution, and, no, using a shipping address as a proxy for residency is not adequate.  Sales taxes are often sold to voters using the traditional "tax the other guy" model; meaning visitors pay a great deal of the taxes.  Check out rental car tax rates for proof of this theory.