Prudential Fox & Roach had the largest market share of residential real estate sales in Montgomery County for the period of 07/01/2009 - 06/30/2010, with 23.06% of the total dollar volume. They sold 1,419 homes for $577 million, with their 2,844 total transactions amounting to $1.19 billion. Long & Foster had the second largest market share at 5.58%, and Keller Williams was third at 5%.