Rhonda and Bruce are putting up an indoor swimming pool. They can either pay the complete $25000 upfront or go for a deferred payment plan over 2 years. There is an instalment free period of 3 months, the monthly repayment is $1450. There is also a one-off establishment fee of $500 and a monthly account fee of $15. In total, what was the excess payment made by Rhonda and Bruce beyond the upfront price?