Just as with my Quick Hitter series on the FAR, my Quick Hitter series on the GSAR is meant to simplify contracting business with the government. This time with GSA.
GSAR 532.904 Determining Payment Due Dates
FAR 32.904(a) gives COs the authority to determine the payment schedule of a contract. Standard protocol is 30 days either after receipt of a proper invoice or government acceptance of goods/services (FAR 32.904(b)). See FAR 32.904(d) for construction payments as such is what this post refers to.
Final payments deduct money lost by the government due to late completion and labor violations, any moneies withheld due to paying less than the legal wage(s), the cost of defects and omissions and the amount listed in the deficiency report.
Acceptance of all construction projects shall not exceed 30 days.
Between payment and performance bonds, the government knows your capability. All deductions are on you and your construction team.
You know now how the government pays. I can help with the proposal portion.
If you think I can help you then email nicholas.s.robertson@outlook.com for your introductory email and free consultation. 
RobertsonKX Business Blog 