In England, there was a "window tax" for 150 years. And also in France, Ireland, and Scotland. The progressive wealth tax at that time was measured by the size of the house. The number of windows (and other openings in France) was used for ease of determining size.
We have had a similar practice in our studio for 12 years - the complexity of a house is determined by the number of openings. For us, the system works very well. Better than if we counted wall space or living space. For example, a façade design for a big garage or a windowless warehouse would cost very little, because there aren't many openings.
With time, the "window tax" was called one of the main causes of unhealthy cities and a "light and health tax," because people built fewer windows to reduce the tax.
There was also a tax on the number of bricks in walls in England. There was a request to increase the size of an individual stone, but the government soon limited the size of bricks in production, and imposed a double tax on larger stones.
There was also a tax on wallpaper. Homeowners dodged it by buying paper without a pattern and applying the image themselves, using a stencil.