Tucson Realty & Trust Co. is merging its residential division with Long Realty Co., the largest residential realty company in the Tucson area, with some 800 agents. Financial terms of the deal were not disclosed.

The merger is a reflection of the national trend among residential firms to consolidate operations in certain markets.

"The margins are shrinking very fast for brokers," says Gary Doran, head of the Tucson Association of Realtors. One way for companies to increase their profits is to "increase their market share," he says.

Approximately 200 agents from Tucson Realty & Trust Co. will join brokers at Long Realty Co., creating a combined agent workforce of more than 1,000. With the mergers, Long Realty Co. will now have about 40% of Tucson's residential market and estimated sales of $2 billion annually.

Tucson Realty & Trust Co. was founded in 1911, a year before Arizona became a state.

The merger was a "strategic move in the best interests of the company," says George H. Amos III, the grandson of the founder.