Yes, there are definitely wankers at every price point and in my experience the more they're paying, the worse and more entitled they are. We have several threads about charging high rates;
this is the first one I found and there's another
here As for the screening, the ads you've seen have likely taken it from US sites where asking for this sort of personal information is common to avoid the law; prostitution isn't illegal here so we have no need to do it, but if you want lots of extra admin to do there's nothing stopping you. I wouldn't ask for any personal details from a punter, and many won't agree to give them for the reason above.
There is a lengthy thread about deposits
here; it started a long time ago, but there are plenty of posts from the last couple of years