Good faith re-establishment of domicile for retired Canadian

[StephenK]

My father is 60 years old, retired, and has lived in Canada his whole life after the age of 5 and coming from Florida at that time. What sort of proof will he need to get to prove that he will re establish domicile in the US in good faith?

[inadmissible]

A history of filing US tax returns and FBARs when required, lease or ownership of residence, US state driver's license, voter registration card, health insurance