My close friend visited a NHS dentist for the first time. She was asked to pay about 20 pounds before she went in and has been given a plan of action (two fillings) that will be done next week. On the plan is a price of 59 pounds I think. Does this mean she pays 20 + 59, or will the 59 include that 20 already paid, meaning she will be asked for 39 pounds next time? Thanks. Just want to be sure.