go for the water meter they have to change it ,if you ask them to change the stop tap they will proberly argue it is chargable as it is on your property,anyway with a water meter you will proberly save money unless you have about 5 people in the house all taking baths and leaving taps running,work it out with the bills you get,with a water meter you get charged for the cubic meter of water you use plus about 80percent of that will be charge for waste water down the drains,I have never lost with having a water meter even when I had to pay £60 to have one fitted years ago