An eligible owner shall be deemed to be in default of the agreement upon:
A. 
Nonpayment of any installment within 30 days from the payment due date;
B. 
Nonpayment of any tax, special ad valorem levy or special assessment which is levied subsequent to the signing of the agreement by the tax district, and which is not paid prior to the expiration of the warrant of the collecting officer; or
C. 
Default of the eligible owner on another agreement made and executed pursuant to this Part 6.
A. 
In the event of a default, the County of Sullivan shall have the right to require the entire unpaid balance, with interest and late charges, to be paid in full. The County of Sullivan shall also have the right to enforce the collection of the delinquent tax lien pursuant to the applicable sections of law, special tax act, charter or local law.
B. 
Where an eligible owner is in default and the County of Sullivan does not either require the eligible owner to pay in full the balance of the delinquent taxes or elect to institute foreclosure proceedings, the tax district shall not be deemed to have waived the right to do so.