MediaVest, part of the Starcom MediaVest Group and the incumbent on the FindaProperty account, won the business after a closed pitch against MediaCom, which handled Primelocation.
The win also includes the online property brand Globrix, a UK search engine for flat shares and new homes that was taken over by the group in January this year.
The Digital Property Group, which claims its combined brands reach 8.2 million property-searchers, recently launched a free Apple iPad app for Primelocation.
Steve Parker, managing director, MediaVest, said: "Digital Property Group is a smart, digital business with a clear goal. We're delighted to have expanded our partnership with them and relish the opportunity to drive further success."