It's not clear what "tax" You are referring to.
Did you leave the state of NJ and then close the sale of your home in NJ?
At closing you should get from your attorney a receipt for NJ Estimated Tax .
That's your documentation proof for including the "exit tax" amount on NJ-1040 Line 57 or NJ-1040NR Line 51 for reimbursement, if NJ asks you about it. You should keep it with your records.
@mdminuto
