How would you find out if a provider will provide a service. Say I want a female provider to use a strap-on. How would I make sure that the provider has that option in their bag O tricks before I setup the appointment? Please, do tell..

Some how you have to communicate with her prior to seeing her to see if she does that.
or
Do a search or read TER reviews and see if a John mentioned the words "strap on" in his reviews.
or
Ask fellow hobbyists you know, if they know of a girl who's into that.
or
I imagine most all post op transsexuals are into it?
But the bottom line is, some how you have to talk to her first and make sure she is up to it.
JH1