The Sims modders. Is there anything they can't do?
No. No there isn't. In the latest example of modding excellence, Mod The Sims forum member simmythesim created an add-on to The Sims 4 (via SimsVIP) that lets players create and manage hotel-like buildings in their virtual neighbourhoods. The new hotel venues can house up to six Sims at a time as guests. Like the recent school mod, this one is a little rough around the edges compared to the stuff you see in the base game. simmythesim notes that guests still have to pay the full price of the lot to move into a room until the next update comes out in the next few days. The creator also recommends installing a pre-existing door-locking mod "so the hotel's guests don't constantly barge into your room."
Given that The Sims 4 already has a luxury stuff pack and some impressively detailed nudity mods, I'd say it's only a matter of time before high-end brothels start running popping up all across the Sims-verse.