The strongest position in a price increase conversation is your own invoice history
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An increase letter is argued in percentages and settled in lines. The buyer who can set last quarter's invoiced prices beside the price list in force negotiates from a record. The buyer who cannot is agreeing to a number nobody in the room can check.
Price Double Check builds that record by email, one document at a time: a buyer forwards an invoice together with the list it should have been billed on, and the lines that differ come back named. Kept for a quarter, those replies are the evidence.
The meeting itself is short and lopsided. The supplier arrives with a cost argument, a date and a figure. The buyer arrives with an impression that things have got dearer, and an impression loses to a figure every time.
The letter carries one number and the quarter carries a list
An announced increase is not, on its own, information. When a supplier writes that prices rise five per cent from the first of March, prices rising five per cent is the one thing in the conversation both sides already know. What nobody has written down is the composition: which lines moved, by how much, and whether the lines that moved are the lines you buy.
The chain this service was built on makes the point with its own figures. Of 382 invoice lines reconciled against the price lists their buyer had been given, 41 carried a genuine price difference. One of them, a single line on a single delivery, was billed at €13.23 against €11.235 in the most recent list that supplier had sent: 17.75 per cent, €47.76, and 91 per cent of the margin on that consignment. A second item was billed at €1.26 from March while the list in force said €1.176, and €1.26 appeared in a price list only in October.
Neither of those is a five per cent increase. The first is a line whose list had never been superseded. The second is a price that quietly became the new normal seven months before anyone wrote it into a document. A letter would have covered both of them and described neither.
What a record of your own prices has to contain
The documents are almost always there already. What is missing is the arrangement: they sit in an inbox as attachments rather than in a table as prices. Four things make the difference between the two.
- Every price list as it arrived, with the date it arrived. The list that applies is the one in force when the goods moved rather than the newest file in the folder, and the reasoning is in the price list in force on the delivery date.
- Every invoice, keyed on the item code. Descriptions do not survive the journey: 335 of 442 lines in that set carried a description that did not match its own row in the price list, and codes turn up with undocumented suffixes that have to be normalised before anything joins.
- The increase letters themselves, so that the announcement can be set against the outcome. The method for that pairing is the increase letter against the next price list.
- Percentages and dates rather than euros, while you are still looking at lists. A line that rose 40 per cent and is bought once a year and a line that rose two per cent and is bought every month are different problems, and the euros become countable only once the invoices are in front of you.
None of that is an analytics project. It is four habits, and a buyer who keeps them walks into the conversation able to say which codes moved, when, and against which version of which document. That sentence changes the subject from whether costs have risen to what was charged, and only one of those two questions has an answer in the room.
Forward one invoice and the price list it should have been billed on, and the record starts assembling itself: every reply names the lines that differ and keeps the pair of documents the finding came from. What a check costs is on the home page.