Hitting some of the things you're looking for, Life on Mars by herminekurotowa on Ao3.

Summary: Jared would never have thought it was possible to find a soul mate in a state-owned brothel, but when he does, it will turn everyone's world upside down. But it's common knowledge that soul mates happen for a reason.

Sold by padaleckifantrash and wincestismyguiltypleasure1967 on Ao3.

Summary: Omegas can be sold to brothels and Jared was unlucky enough to present as an omega in his time at a foster home. Jensen runs a successful brothel and buys the newly changed teen.