Tax laws vary greatly from state to state.
In Illinois, the use tax is due a short time after any purchase if greater than $600, otherwise it is due at the end of the year. Needless to say, most of your aircraft purchases will be due right away. If you don't pay until they find out about your airplane when you register it, they will hit you with penalties for late payments. A build over many years will accumulate stiffer penalties.
On my first airplane, finished in 2010, they even audited my airplane purchases over a four year period to verify I had really paid all the taxes. I had to show them all the receipts for the airplane by year purchased and when paid. I passed, but it was a thorough examination.
All the states that collect use taxes have become very aggressive in collecting with the helpful aid of your FAA registration.