What a restring actually costs you
You buy string by the reel and sell it by the racket. Somewhere in between sits a number most shops carry in their head — what a set actually costs — and it is usually a little out of date. Which makes "what did I make on that job?" a question you can only answer by sitting down with a stack of receipts.
Racketworks now tracks what you actually paid. Say a reel costs you $160 and gives you 16 sets: the product knows a set off that reel cost $10. Log a restring, and that $10 leaves the shelf and lands on that job — and it stays there. If the next reel costs more, old jobs keep the cost they were actually strung with, because that is what happened. Mark string as ordered and receive it when it arrives, and the price comes in with it rather than being typed twice.
What it refuses to do is the part worth reading.
Where a job never recorded a cost, we show you no profit at all rather than a flattering one — a guess would report margin your shop never made. Every profit figure carries how many jobs it is actually built on, so you can see whether a number is worth trusting. The "jobs per reel" figure won't average off a single reel; it shows a dash until there is enough to mean something. And a customer's own string, sitting on your shelf with their name on it, never counts as your cost or your stock value — it isn't yours.
None of that is difficult to build. It is just a decision about whether software should tell you something confident and wrong.
What it doesn't do yet. Labor isn't in the margin number — this is the cost of the string, not the cost of your time. We also haven't settled whether shipping and sales tax should count as part of what a set costs you; both are real money and shops split on the answer, so we would rather decide it deliberately than pick one quietly.
Where to start. Put the cost on the reels already on your shelf — Inventory will show you which ones are missing it. The next racket you string on any of them books a real margin, and the reports start filling in from there.