I used to do this at one point.
We would get passed a "decline" book from a mainstream finance company then try to place the deals elsewhere, with subprime usually.
However one of the companies we used offered personal loans, some of the declined deals we had, had nothing to do with the person having bad credit or whatever, but none of this was ever explained.
So we would ring the dude up and be like, you know you got declined for finance, we can place it for you, it'll cost X amount, the rates were actually not terrible, but you could literally just apply for a personal loan yourself for maybe 2-3% interest cheaper.
But people don't know, so we would place it on a personal loan, perfect prime credit customer and they would get charged 2-3% over odds and we would get a nice commission off it, usually about £1500 a pop.
The whole sector was dodgy AF though, pre FCA regulations so, about 2010-2013 (something like that) literally the wild west of finance agreements. I could tell you stories of all sorts of really dodgy stuff that went on.