I don't personally ask for deposits but what works for me is not what works for everyone else and everyone should respect a reputable lady who asks for one.
I believe there is a thread BBG started here that links to the Twitter accounts of all of Upstate NY's providers; most of them DO ask for deposits and for those who don't want to do deposits, that's fine, they're getting paid anyways so just stick with a provider who does things you are comfortable with
Also, I've seen the screenshots. PLEASE do your research on providers before you book with them!
You should ALWAYS look for the following:
* REVIEWS (even if girls have a no-review policy, there is always *something somewhere* about how her services are)
* ONLINE PRESENCE (a lot of providers use Twitter; for those that don't, you can look back on ListCrawler/EB to see a provider's previous ads and the dates/times they were posted)
* REVERSE IMAGE SEARCH (take the provider's photo and plug it into google! a lot of catfishes are using photos of actual providers and models, and finding them online is pretty easy)