(2) within 30 days of first delivery by DomainTools of the Enterprise Services. and (3) in accordance with remittance instructions in any invoice provided by DomainTools. Payments under an Enterprise Quote are due and payable whether or not DomainTools provides an invoice. Beginning the day after a payment is due, interest will be due and payable by Enterprise Customer at the rate of one and one-half percent (1.5%) per month on any unpaid amount. Payments are nonrefundable.