Russian billionaire Valery Kogan, spared no expense in making sure his granddaughter, 19
Mariah Carey and Sir Elton John were paid around £3.5million to sing at the wedding .
The pop legends were the highlights of a nine-hour extravaganza as 19-year-olds Irene Kogan and Daniel Kenvey wed on Saturday.
Mariah Carey is said to have been paid £2.5million to fly in from the US and sang ballad We Belong Together to them at
London’s Landmark Hotel.