I tried this last night, just for the hell of it. Found a motel room at the Sunshine Motel. It actually only cost me $19 because I got the room through Hotwire and when I got there it had some severe water damage and a hole in the wall, as well as mold on the ceiling and some weird blue-ish stains on the shower curtain, so I got a nice discount.
I posted an ad on Craigslist's Adult section. I did the whole discreet-sounding deal with the "Roses" instead of dollars idea. The first victim, some old man named Paul, actually showed up with 120 roses. We watched Deal or No Deal for an hour and he left. I sold the roses to a florist this morning and netted twenty bucks.
The second interested party, Quentin, showed up, and everything was going swell. Until I found out he was a eunuch. After that I didn't know what to do, so he left awkwardly. I gave him a 30 dollar refund on the half hour, so I had made $30 at that point.
The next guy that came in was a transvestite. Being a woman myself, this was quite the turn-off, so I didn't really let anything happen. But I gladly took the money for the fifteen minutes. Total profit then was $60. $80 with the roses.
Victim number four tried to rape me, but I got the better of him and stabbed him right in the jugular. Luckily the carpet was already a nasty shade of maroon, or I may have had to pay a damage fee. Hollowed out the mattress of the most unappealing bed and stuffed his body inside. But I got his money and his wallet. Total profit, with rose money: $142, a coupon to Steak N Shake, and a MasterCard in the name of Christopher ********.
I was satisfied, after that, so I checked out with what I had left of my dignity, returned to my house, and fell asleep, much richer. This method DOES work!