On these cold nights 3 hot water bottles. Sleep upstairs, bathroom also there and book shelves, on one shelf l have a tray with electric kettle 1.7ltr which l fill with water from the bathroom opposite, plug in and boil, it will turn itself off if l don't do it before then fill my bottles. Also on the shelf is a mug, teaspoon and coffee sachet so if l don't want to go downstairs to the kitchen l can make myself a hot drink. Please beware throwing rubber hot water bottles anywhere especially when filled with hot water, l threw one on the bed it bent under at the neck and split both sides, result- hot
water poured out, wet bed had to be changed.