A 30-year fixed rate–mortgage is available now at 7% APR. Monthly payments (360 of them) will be…

A 30-year fixed rate–mortgage is available now at 7% APR. Monthly payments (360 of them) will be made on a $200,000 loan. The realtor says that if you wait several months to obtain a mortgage, the APR could be as high as 8%, “and the monthly payments will jump by 14%.” Is the realtor’s claim true? If not, what percent increase in monthly payment will result from this 1% increase in APR?