Are You Free Friday, or Should I Bring My ATM Card?

So in German, as in English, you can ask for an appointment by asking, "are you free...?" or "Do you have time ..?" If you want to ask a woman on a date, you have to say "Do you have time...?" or she'll be offended that you're implying she's a prostitute with a fire sale. I'm not sure if actual prostitutes are offended if you ask them if they're free. If any of you find out, feel free to let me know -- my language studies aren't really going into that area. Just FYI for any of you planning on being social when you visit!