Nearly three and a half years after workers began stripping hazardous materials from the former Deutsche Bank building near ground zero, officials expect the project will finally be finished next week.

But according to officials and regulators, the demolition of the 26 remaining stories of the structure, which stands as a grim reminder of the terrorist attack, will take at least seven more months, with the final price tag soaring to an estimated $300 million from $45 million in 2004.

The deconstruction of the hulking tower has been marked by the most stringent environmental restrictions, as well as delays, regulatory failures by city agencies, criminal investigations of contractors and the death of two firefighters in a blaze two years ago. Yet, even as the work lags behind the most recent timetable set by officials, the end now appears close.

“It’s way too late, but at least we’re nearly there,” said Councilman Alan J. Gerson, who heads a City Council committee overseeing work at the building. “It’s time to get this job done once and for all.”