You will need $US10 per person for your Tourist Card ( entry ) and $US20 per person for your Departure Tax, I would either use your debit card once there in the ATM which only gives out pesos and at a very good exchange rate, but do inform your card provider the dates you are in the DR as otherwise they will block your card for f raudulent use or you can take GBP and just change that there at the local cambios at a far better rate than you will get here in the UK. If you change your GBP at the hotel you will get less pesos than going to the local cambios.

Angie.