I find it is best to ask when you are being offered B2B and negotiating the price before she removes her clothes ,chances are she will say yes just in case you opt for the hand job without B2B and she loses out on the extra cash , plus she might like the fact that you want to eat her pussy as it gives her a 5 or 10 minute break. Most of the massage ladies i see or have seen apart from(the old lode lane ladies) are happy to let me have a munch ,it also helps to slow things down and prolong the experience in the room.
Totally agree with Seandana on this subject.
If it is someone I have never seen before, but has the body shape I like, I will ask if B2B is available. I prefer to take control with this as I don't like it when you get the B2B offer with only 20 minutes left and all you get is her standing naked at arms reach.
I have a couple of massage regulars who know exactly what is going to happen during the hour and are either stripped off before me or let me undress them. These are not FS punts but a proper FBSM experience where we both get involved.
Before you ask I will not be revealing who they are as it as a result of playing the long game and I have put the time and £££'s in.
With a bit of research you will soon find which shops offer extras and which ones are legit. Stick to going rates (£40) for B2B with HE and don't pay more if the want extra money for RO.