Kofi, the commercial manager, needs the concrete and excavation quantities by Thursday. Rex, the new assistant engineer, says he'll have them by Wednesday. He says that a lot.
Valuations
The back alley's bill so far: 120 weeks · See the bill
Every month somebody measures the money from me. Measure from the current me, and get me accepted, or nobody gets paid.
The wrong way
Rex measures the basement from the copy in his downloads folder: C02. A fortnight ago C03 went on the published shelf, and the basement went two metres deeper.
Kofi's valuation goes in. The client's quantity surveyor measures from C03. The two numbers are £40,000 apart, and each side is sure the other can't count.
The design package goes to the client for the milestone payment. Rejected: wrong file names, two models missing.
Fixed and sent again. Rejected again, by a different reviewer with different comments. Kofi starts to think of the parcel as a pet.
It's accepted. The money arrives six weeks late. Finance asks why the job is £400,000 overdrawn.
Kofi: Because a file name was wrong.
Both sides measured right, from different drawings. And a wrong file name held up £400,000.
+3 weeks on the back alley's bill: Measured from an old version, and a package nobody checked against acceptance: a fortnight arguing and six weeks waiting for the money.