SCHENECTADY — Bombers Burritos will relocate to a larger site on State Street, purchasing a three-story building for its business rather than renting space within Center City, the Metroplex Development Authority announced today.

Bombers’ owner Matthew Baumgartner will buy 447-451 State St. from Metroplex for $500,000. He will pay half the price at closing and the remainder over the next 15 years.

Baumgartner plans to convert the former James’ Boxing Gym into a restaurant on the first floor and banquet space on the third floor, using a $250,000 loan from Metroplex and $420,000 of his own money.

In addition, Metroplex will provide Baumgartner with a $40,000 grant to install sprinklers on the three floors and to fit-up the restaurant. It also will provide him with a $75,000 facade grant.

Metroplex Chairman Ray Gillen said the building’s 100-year-old facade requires a complete makeover. Baumgartner has told Metroplex the restaurant will employ 15 people by 2010. Metroplex renovated the 7,620-square-foot building with skylights and new windows in 2007.

Bombers was originally slated to go into the ground floor and basement of the Grant Building. The building, which was built in 1928, stands in front of the more modern Center City complex.

Metroplex gave Bombers a $20,000 facade restoration grant earlier this year for the Grant Building project.

The State Street building Baumgartner is purchasing was initially going to house LaSartoria, a men’s, women’s, young women’s and children’s apparel store. Vincent Montesanto was to purchase the building from Metroplex for $250,000 and Metroplex would have provided him with a $375,000 loan at 5 percent interest to pay for renovations. He planned to employ five people by 2010.

Montesanto will remain in downtown Schenectady and open his new shop several feet away from Bombers, Gillen said. Montesanto has been in business for some 20 years and has operated a shop on Broadway in Saratoga Springs since 1991.