Challenge them. And remember that ?30k does not buy windows for a flat, ours is a 2 bed on a peninsular of a block, ie. windows on 3 sides plus French windows on to a private balcony, and they did new doors. Price in 2009 ?8,500 ish. So challenge everything and ALSO be ACTIVE in your estate and attend the weekly site office meetings which will be held in the builders' site offices on the estate, and if you can not attend them demand to see the Minutes of the same. On our estate only two of us ever attended those meetings and they were invaluable.