I’m only used to federal construction grants, so I may be a bit off. But I assume that you’ll have to be able to do not only the actual work but all of the federal paperwork. There are standard processes for reporting, filing, invoicing, and probably more than a few other things.
For instance, in cycle one of the Federal Safe Routes to School Program, applicants were told: "Refer to the LAPM for guidance in delivering a federal-aid/SRTS project. . . must be in compliance with applicable provisions in Title 23 and 49 CFR part 18 and part 19 respectively. 49 CFR is the Uniform Administrative Requirements for Grants and Cooperative Agreements to . . . "
You have to meet EEOC, ADA, and sealed bid regulations. You could spend as much time verifying that your office practices meet federal requirements as you do doing the job, if it’s a small one. You may have to submit performance bonds covering the cost of someone else doing the project if you can’t see it through (very standard).
On the other hand, most Departments that manage grant programs have local area reps that can help you get through the red tape. In our area, Caltrans manages the federal construction grants and their Local Assistance office has classes on how to work through getting and fulfilling a grant. Free classes. Usually only once or twice a year, but free.
If you’re interested, your next step would be to identify a grant that interests you and to contact the department managing that grant program and ask for advice and help. If you’re small, you may qualify as a DBE (Disadvantaged Business Enterprise). Meaning you’re small and have no clout. Getting qualified as a DBE may get you a job subcontracting for a larger company that had to seek out DBE’s as a requirement for getting their own federal grant. At least that’s the way it works for construction grants.
You’re not going to know whether it’s worth it to go for federal grants until you know what hoops you’ll have to jump through to manage a federal project. And that will be Department specific, in at least some ways. I’d recommend looking into it, but then I enjoy looking into things. And once you have the processes in place, they’re there for the next grant application as well.
Oh, and they can audit the project when it’s done. You won’t be paid for any help you provide them during that. Not every project gets audited, but you have to assume that it might when calculating your estimates.