GNMAs were .gov paper that you could cash trade at brokerage houses at $35 per million.
I once worked at a place that had a retail broker marking up GNMA paper with 2 points ($20) per $1000 face. He was in cahoots with the debt buyer at a large insurance outfit. The manager knew what was going on at the brokerage but did not want to stop t because the office was so productive. I have no idea what kickbacks may have been involved. All parties are now out-of-business.
He also had another broker guaranteeing old ladies that oil & gas partnerships had "guaranteed" 8% returns. One of them sued and lost because of the lies told by the brokerage.
The Firm was a former commodity outfit known as Thomson-McKinnon. Crooks everywhere there.
0 per $1000 face.--+++