Auckland lawyer Barry Hart appeared in the Auckland High Court on Monday to dispute debts being claimed by the ANZ National Bank.
Mr Hart has been struck off the register of lawyers after being found guilty of misconduct, but is appealing against the decision.
The ANZ National Bank is seeking a court order defining how much debt Mr Hart owes and wants the authority to repossess the house he lives in.
A lawyer for ANZ told the court Mr Hart secured several loans totalling $30 million for the purchase of several properties.
She says Mr Hart defaulted loan payments so the bank sold some of the properties under a mortgagee sale.
The court was told Mr Hart owes more than $4 million for the property he lives at with his wife.