Davis-Bacon covers construction, alteration, and repair work on federal contracts and sets a prevailing wage floor by trade and location through a wage determination, similar in spirit to how the Service Contract Act works for services. Rates can vary significantly by county and by trade, a carpenter and an electrician on the same job site can carry very different floors, so you need the determination for the exact location and trades involved, not a general sense of the going rate. Certified payroll reporting usually comes with the territory, so budget the administrative time along with the wages themselves.

In a sentence

"Laborers and mechanics employed on this contract shall be paid not less than the wage rates in the attached Davis-Bacon wage determination." Pull the wage determination for your specific location and trades before you price the job, since guessing at prevailing wage rates is a fast way to underbid yourself.