- procurement
- construction
An opinion of probable cost is the design engineer's structured estimate of what a public project will cost to build, prepared before bids come in. It rolls up quantities and unit prices into sections and subtotals, then adds markups for contingency and soft costs — a document precise enough to budget against but explicitly an opinion, not a bid.
The OPC is the reference artifact of the platform's extract stage: the six Tetra Tech roundabout estimates it reconstructs from a scanned bundle are OPCs, and the extraction model is built to hold any contractor's section-and-markup structure without hardcoding one firm's taxonomy. Because the OCR text layer of a scanned OPC garbles digits, its figures are read from the page image, and each extracted value carries its page provenance — a dollar total is [verified] from the sheet, an uncertain quantity marked approximate. It is the cost counterpart to how a project is procured, whether by construction manager at risk or competitive bid.