Default mortgage servicer and due diligence firm Clayton Holdings is increasing its stake in REO investments. The Connecticut-based property surveillance company announced plans to acquire Green River Capital, a provider of REO and short sale services, for an undisclosed price. Business at Utah-based Green River is booming. The company recently initiated a plan to rent out REO. In March, Green River became one of three firms handling REO sales for Freddie Mac. "During the past year, our REO and short sale assignments have grown by more than 87%," said Christopher West, CEO and founder of Green River. "By joining with an industry leader such as Clayton, we expect to continue this growth and create a more scalable company while increasing the strength of the Green River brand." Clayton said Friday in a statement things would change very little at Green River. Its 200 employees will likely remain and the management team kept intact. West will share the chief executive space with Clayton CEO Paul Bossidy, Joseph D’Urso will remain president of Green River. Bossidy added that the acquisition will expand Clayton's loss-mitigation offerings at a time when short sales and REO dispositions are both expected to remain strong. "Green River’s BPO offerings will help our clients, along with our Quantum special servicing unit," Bossidy said, "to make better loss mitigation decisions and will complement Clayton’s diligence and whole loan acquisition services." The transaction will close in 60 days. Write to Jacob Gaffney. Follow him on Twitter @jacobgaffney.