first of all,welcome to the forum.
Depending on where you are in uk there are different price structures but for an approximate quote here goes 450 for fixing tiles and tanking,if it is only shower area you could charge 50 plus the price of tanking kit but only if you can start your tiling while you are waiting for tanking to dry,otherwise you will need to charge your day rate as you will be wasting a day tanking.
check threads under tanking for more info and prices but i'm sure i wont be far away with these prices,Happy Tiling

Bri