The only thing you can expect to an emailing asking "will you have sex with me?" is to be put on her DNS list.

So why not PM her reviewers who got "extras" and ask them? They have no reason to lie to you, so yes I would believe them. You might also ask if "extras" are an upsell or part of her normal session.

That when FBSM providers say "no sex," generally they mean "no vaginal intercourse."  HJ finish is almost always included. (If it wasn't, why would you see a FBSM provider?)  Russian is another activity that is popular.  BJ, not so much, but is possible, but usually only with repeat clients.  

But of course every girl is different, and, as they say, YMMV.

....I have had spontaneous sex with three of them-unannounced and unsolicited. Now, one of these ladies NEVER does it, but did with me. Another one might do it with someone she felt attracted to. The third I believe is in her repertoire. The point is, is if you are nice and professional and use a touch that works for her (Bid YMMV here), magic can happen. Of course, most of the time, all you get is a handy!

I saw a lady in my area who advertises massage only (for obvious reasons) but who does Russian, HJ, no BJ but it was great.

I read all her reviews before booking, so I knew exactly what I was in to, and that's exactly what I got.

and go with the flow when you meet her. FBSM is usually "no sex" meaning no FS, but it usually does include some release (HJ, BJ, etc..).  

As GaG said, you could always PM a reviewer or two and find out the real deal if you are feeling unsure.

It is safe to say that most FBSM girls will do something with the boner, on the flip.  
     And, of course, YMMV, depending on what she is presented with.

It may be a recipe of hand, tits, mouth, face, ass cheek, feet, throw in a filthy story, and
the possibilities are endless for Happy Endings.

*"NO SEX" means "Do Not put Boner in Vagina"

FBSM? SMH.  

Go get yourself some full service. You'll thank me later