knock down

fe’l verb

1. To hit or knock (something), intentionally or accidentally, so that it falls. As I took the can off the shelf, I knocked down the one beside it.
2. To demolish. We knocked down the garden shed when we moved.
3. At an auction, to declare (something) sold with a blow from the gavel. The picture was knocked down for £50.
4. To reduce the price of. They knocked it down by another £5, so we bought it.