When I was in my early 20's I was offered lots of material objects for a sexual relationship with a very old and extremely rich Asian woman. No joke. Of course I did the right thing for me....
Declined all offers. I knew my self worth. It was tempting. I think just not having these types of people in your circle is a good start. Sometimes it's tough to see what people are really up to at first. I don't think it's only men that do this to women. I don't really know.