Look for the tug of war between proponents and opponents of extending high-cost loan limits for Fannie Mae, Freddie Mac and the FHA to go down the wire and even heat up when Congress returns from its summer break in September, Hill watchers predict.Unless Congress intervenes, the “emergency” high-cost market conforming loan limits that were enacted in 2008 will expire on Oct. 1. That would drop the top Fannie, Freddie and FHA loan limit from the current maximum $729,750 to $625,500.