I thing my gas is a rip of what do u think?

I live in south wales in a 4 bed house with a loft conversion, the walls are insulated and we have double glazing ... we have 12 radiators in the house and a gas hob the water is heated with gas too with a baxi combi boiler ... when we bought the house they already had those key meter things and swalec wanted over �200 to remove them so we kept them in .... but we have the heating on a timer to come on and off 4 times per day but its costing �70 per week that cant be right ?????