Paid search is the one channel where the economics can be worked out in advance, on paper, before any money is committed. It is a short chain and every link is measurable.
Start with what a signed case is worth to the firm. Divide by the margin you need, and you have the most you can pay to sign one. Then work backwards: of the people who click, some contact you; of those, some are cases you would take; of those, some sign. Multiply those three rates together and you get the share of clicks that becomes a case. Divide your maximum cost per case by that share, and you have the most you can afford to pay for a click.
Compare that figure to what clicks actually cost in your market. If the market number is higher, no amount of campaign management will save it — and you deserve to be told that before you spend, not after.
This is why we insist on case economics before touching the account, and it is why the improvements worth making are usually not the ones firms ask about. Lowering cost per click is one lever among four. Raising the share of callers who qualify, or the share of qualified callers who sign, moves the same equation and is frequently cheaper to fix — which is why intake keeps appearing in a conversation about advertising.
The rates in that calculation are specific to your firm, your market and your case mix. We measure yours during the audit rather than working from industry averages, which vary too widely to plan against.