A Surrey ex-dairy farmer now rents his old buildings to a brewery and a boxing gym. Letting buildings is the most common and most profitable diversification on English farms. Here are the real rents, how to price and pick tenants, and the planning, tax and insurance traps to avoid in the UK, US and Canada.

The EU milk price fell 19.7% in a year while farms made 3% more milk, and UK buyers are cutting again. Here's how real dairies sell part of their milk where they set the price, and the honest costs and rules to check first.