The maths we’d wantif we were buying.

Most of the numbers in this category can't be traced to anyone who measured them. Here's what survived the check — and what the tools really change.

Everything we look at first, in the order we look at it. No tools required beyond the ads manager you already pay for.

Salary is roughly six-sevenths of the story. Here's the rest of it, worked through — and the point where in-housing genuinely becomes the right answer.

Work out how many creatives your account consumes per month before you decide who should make them. The number is usually bigger than the plan you're being sold.