All I know is a guy doing government contract work farmed out some work to me. This was mill work. Everything he did needed either plating or painting, and everything needed identification stamped with part number and manufacturer's number. So there is quite a bid of initial cash outlay for stamps and paint. A lot of the stamp and paint requirements are different from job to job, some jobs want 1/16 size stamps, then 3/32, 1/8 etc,etc. The paints the same thing and they don't keep forever.The stamp sets are $350 each. Everything needs to be
individually packaged and labeled. I found the guy to be very honest and he said that the market was getting saturated, driving the prices down by the week.
(Just like here). Even with lowering his rates, he was bidding 100 jobs for every one that he got. He would send me prints and actually show me the government
price, and ask if I could do the work for that price less 10% for him, usually my answer was NO. The jobs he did win I think he was bidding well south of $30 an
hour machine time. Also there weren't enough profit in them to send anything
out other than plating. So you would need to invest in all the money it would take to paint, stamp and package yourself, and be lucky to get $20 an hour.
Did one job for him and said "I would only have made $22 an hour, if everything went right", his comment " That is good these days". I believed him when he said he was only marking up my work 10%. Don't worry I am not posting this to discourage you, I am being honest. Also all material needs to be certified domestic, in a lot of cases you have to hunt around to find the material made in the USA.