Boston Private Financial Holdings signed an agreement to buy 80% of value equity manager Dalton, Greiner, Hartman, Maher. The remaining 20% of Dalton, Greiner will be kept by that firms management team, according to news releases from both companies. Boston Private agreed to pay $75 million up front, with a final price to be determined by various factors. The transaction is expected to close in the third quarter. Dalton, Greiner manages $2.2 billion in institutional assets. Boston Private, through various subsidiaries, manages $6.8 billion, largely for high-net-worth individuals but also for some institutions.