The number on the front of the data room is the one number you must not trust.
A seller's broker leads with the same figure every time: last twelve months' income. Take a catalogue whose pack opens with £280,000. Multiply by a and you have a price in thirty seconds.
That is exactly the trap. A buyer is not paying for what the catalogue earned last year, they are paying for what it will keep earning for the next twenty. Those are different numbers, and the gap between them is where the deal is won or lost.
Last year's £280,000 might include a sync placement in a national ad that will never repeat, a viral moment on a short-video platform that has already faded, and a fresh-release bump from a deluxe reissue. Strip those out and the catalogue might really throw off £200,000 a year, the figure that actually recurs.
Your job, before any multiple or touches the page, is to build that recurring figure: the sustainable run-rate. Normalising income is the unglamorous work that decides whether you overpay by a third.