I cannot give you any advice on rates, but I can say that you should have an understanding on how long it will take to get paid for your work. I have not worked for the Post Office, but we do work for the BLM, Forest Service, ASCS and GSA. The GSA seems to be the slowest pay, up to 4 months, and they don't pay interest. some agencies will pay cash if the amount is below a certain dollar amount. Sometimes we have billed a job using different invoices, to keep below the limit. Ask for payment in cash. Put your tax ID # on the invoice, and make sure to report the sale on your taxes. I do not give government agencies a discount for early payment. They don't pay on time, but do take the discount. We normally add a bit when dealing with the government, just because of the hassle. Make sure the person who gives you job approval actually has the authority to hire you. Make sure all invoices are signed by the person who has the authority. Don't do any more than the contract calls for unless you like to work for free.
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