The difference in monthly payment (p&i) on a $200,000 mortgage if rates go from 3.4% to 4.4% is $114.56 per month. The Mortgage brokers association, Freddie Mac predicts rates will be at 4.4% by the end of 2013. Take $114.56x 30 years and you're looking at paying $41,241.60 more for the same house if rates go up by 1%. What if they go up by 2%? Now would be a good time to get off the fence and make that purchase!