bit of a hit miss question,without looking at a job as the price could vary,i mean what type of pool is it,as there is all the bonding to be done which costs,price of armoured cable and all other bits to terminate the cable, plus rcd,people go out and do ther own work without considering all the important bits that go with the job which gives us electricians a bad name.sorry for the rant! But i would be looking at around £400 at a guess with no idea what the jobs like.