I received a business card from a streetwalker. It said "Mia 555-5555" That was it. Name and nuimber. I kept it in my wallet for years as a novelty. I'm sure she must have had some regulars that used the card, and if anyone else just happened on the card, and called her, what would they say? "Hi is this Mia? I found your card. What business are you in?" She would probably hang up or lie. Anyway I thought it was actually funny. It was the only time I have ever seen or even heard about a "hooker business card." Never saw or got one from an escort.
That was back in the day when few people had cell phones. In this day and age when people not only have cell phones but most people have smart phones, I rarely even see people in other legit businesses even pass out business cards anymore. They just trade numbers and input it in their phones.