An Office building is listed for sale at $500,000. You can borrow 80% at 6% interest amortized monthly for a 20 year term and put 20% down. Your required unleveraged IRR is 10% and you want to use a 9% terminal cap rate. You plan a five year holding period after the purchase. You have calculated the annual pre-debt service NOI for each year as: Yr. 1 = $40,000 Yr. 2 = $41,000 Yr. 3 = $42,000 Yr. 4 = $43,000 Yr. 5 = $44,000 Yr. 6 = $45,000. Using debt financing, what is the Year 5 loan balance?