I have just bought my first flat in London that I am converting into a 4 bed. The whole CH system is old as is the old Glow Warm Boiler (think this was installed 6 or 7 years ago). Am told Worcester Bosch are excellent but pricey. Am thinking of a Potterton 28 ? Any recommendations (its a rental flat, single floor but hopefully 4 residents so needs to be relatively efficient). This seems a minefield and I am on a tight budget. Was hoping to source the whole heating pack inc boiler and copper tubing for less than £1000. Help!