"It's a good alternative to a Financial District price point," says GVA Williams principal John Hennessey. Even in anticipating a rent in the high $30's per sf, the sublease would represent a substantial discount to Downtown, relays Hennessey, given that asking rates there are beginning to scrape $90 per sf. Considering the high-end quality of the space, Hennessey says the economics should be especially attractive to Financial District tenants because that core market is just a 10 minute walk. The eclectic North Station area is even closer, and is fast becoming a chief beneficiary of the $14.8-billion Big Dig project. New residential, restaurants and retail options are springing up daily, and North Station is also home to a major regional transit center and thousands of parking spaces.

On the latter matter, 80-100 City Sq. is adjacent to a below-market parking lot available to tenants, and has immediate access to a ramp for Interstate 93. Logan International Airport is a five-minute ride, Hennessey estimates, and there is also an aqua alternative thanks to a nearby water taxi stop connecting to the airfield. Transit convenience was among the factors cited by Keane when the company leased 80-100 City Sq. in 2001, and Hennessey notes that the area has since significantly improved on that count.

Once among Boston's grittier neighborhoods and dominated by industrial uses, Charlestown has gradually seen more office product developed in the past decade to where it is today about a 3.2 million sf submarket, according to GVA Williams. "The numbers are really quite strong there," says VP Chris McMahon, who is handling the Keane assignment with Hennessey and GVA colleague Steven Lombardi.