If you have ever been tempted to change flats in order just to obtain a balcony, today’s invention is for you.
A box about the size of a smallish filing cabinet, but curved, would arrive in the lift. This would be bolted to the floor of your flat and therefater act as a breakfast bar (or bar, full-stop).
When the weather was good, you could throw open a window and extract from the bar, a set of telescoping, circular segments, each with the same u-shaped cross-section.
These would extend outward through the window, forming a sturdy, projecting balcony.