I have enough money that ~$3-7k/month doesn't make a large difference. I've never bought anything additional for them unless you count paying for dinner and drinks and Ubers.

Youth is definitely a top draw. You might have seen this study: https://www.nytimes.com/2018/08/15/style/dating-apps-online-... - men of all ages send most messages to 18-19 year-olds. But there are other factors: not my experience but some men have fetishes they want to fulfill or they want to cheat. I'm actually doing well enough on Tinder to meet a new, above average girl every day in a big city. But I'm not in the social circles that would allow me to meet top current models or ballet dancers... But this makes it possible.

It's just my impression that could be wrong but I'm 90%+ sure that none of the girls I was seeing had other "clients." I'm picky and I avoid girls who seem like "party girls" and have no job or don't go to school. Also, only one of them had a previous arrangement and all of them wanted to have chemistry first. They describe most of the other men they met as weird and unattractive.

So I agree with you that you can't trust 80%+ of them if you care about not being just another client.