well hi sorry about bringing up flies again but thought i would update everyone, Charlotte from "sin mosca"  came to spray around our casa for free as she said she would and she did say when she came that it probably wouldnt be 100 per cent effective as our place is still a bit like a building site - not bad but a heap of sand etc but she said  :o it would improve the fly situation dramatically. Any how I have to say sorry Charlotte the only effect it seemed to have was to encourage more flies, we actually did seem to have far more flies after the four days than ever before and it was even commented on by neighbours, so my advise is listen to peoples actual experiences before parting with your money, but as i stated before the after bite spray did work.