our 15-year old daughter has been selected to attend the Keele International Soccer Cup in late July
You have received great advice from other responders. I don't have much to add, except this:
Yay Parents! for making it possible for a 15-year old to take her first big international trip. I took my first international trip when I was her age, and it
changed my life in all sorts of positive ways. There is nothing like going someplace and seeing it for yourself, especially when one is still young and full of energy. I came back from that trip with new confidence, new maturity and a greater appreciation for the life I had with my family in Kansas.
You are giving your daughter a gift beyond imagination, something that she will remember the rest of her life.