1) don't know exactly about the Amend Undo stuff...never did it myself, I only know where the help page is.
2) IF you do attempt to sue them in the coming years.....remember that only the property tax portion can be used as the deduction. Any flat fees are not allowed to be included. For example, the NC vehicle reregistration includes the DMV fee, City Property tax, County Property tax, and some cities also have a flat re-registration fee. but only the two actual property taxes can be included in the TurboTax deduction. Other states probably do things differently, so you'd have to parse out the proper amount yourself.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
