They spent $140,000, within 2 percent of their budget, and got more house for considerably less than contractors would have charged.
The contractor charged $105,000, and they had spent another $35,000 for materials.
The investigation report said large military contractors routinely charge the Defense Department for hundreds of millions of dollars paid to consultants, often without justification.
The third contractor was reliable, but charged more than the previous two.
Mr. Hevesi said some contractors had charged the full $240 even though their costs were far less because they installed substandard toilets.
Preliminary results show that for the first week, city workers in Queens cut down 51 trees, for which the contractors would have charged $10,688.
Both general contractors and construction managers usually charge a percentage of the cost of the job, or in some cases a flat fee.
By picking up ineligible riders, the contractors can assign more buses to a route and thus charge more.
Black contractors charge that many companies owned by men will merely appoint a woman as a figurehead owner to reap the benefits of affirmative action.
Interior believed that the fees the contractor would have charged were excessive and the savings were uncertain.