In my experience £70 is nearer the mark.
Really?
In your Review you stated you were asked for £50 but paid £40 for B2B. So exactly the same.
£40 is "industry standard" (on top of the massage price).
What there is no "industry standard" for is what B2B consists of.
Depending on the girl, it can mean standing naked by the table through to sliding on both back and front with AAA .... with all variations in between those two extremes, e.g. some will keep knickers on, some will just rub their breasts against you, some just slide down your front, some your back, some allow external touching, some allow internal touching etc