Owners of the growing real-estate firm Peregrine Group LLC, of East Providence, have paid $30.2 million to acquire more than 30 residential buildings across the state from members of the Gemma family, who will continue to hold an ownership stake in the properties.The purchase includes 530 apartments in eight communities, which doubles the apartments Peregrine's property-management team now maintains, said Colin P. Kane, who co-founded the company 15 years ago. Kane [...]