She says a "small" deposit..... If that means 10/20 quid I would not rule out stumping it up if I really wanted to see her and I was content with the mechanics of making payment with respect to discretion/anonymity.
I can't see any financial difference between losing a tenners worth of petrol being stood up after driving over or being scammed out of a deposit..... At some point we have to have a leap of faith, set off and hope she's there and as advertised.
At the end of the day, it's not hard to cultivate and maintain a basic AW feedback profile - if you can't or won't do that, you just have to accept that some SPs on there will put up some obstacles, hurdles or hoops for you to negotiate (or flatly refused to see you).