I was on craigslist and I met a guy.
Do you consider this hookup to be casual?
Yes, and there was an agreement made that he would pay me. I did find him attractive and he was good in bed.
I'm not here to judge you either way about receiving payment in exchange for sex, but it's important that both adults consent. Meeting online makes sense because that's happening more often with technology today.
I think he planned on robbing me.
That's awful that he planned on robbing you. You should avoid contact with this person in the future, as he might be successful in robbing you and much worse. You need to be safe and protect yourself.