<p>You catch it by pricing the change the moment it&#39;s proposed, not after it&#39;s installed.</p> <p>Mid-construction swaps blow budgets because nobody re-runs the numbers fast enough to see the impact before the crew mobilizes. BidLight is built to close that gap:</p> <ol><li><strong>Update the model, not a spreadsheet.</strong> When the finish changes in Revit, update the model directly. BidLight reads geometry and metadata in real time, so the cost impact isn&#39;t a separate exercise someone forgets to do.</li><li><strong>Let the AI reclassify the line item.</strong> Our two AI models re-tag the BOQ entry automatically at roughly 86% accuracy, so you&#39;re not manually re-mapping quantities to a new material.</li><li><strong>Reprice against current data.</strong> The new finish gets pulled against our ~$30,000 pricing database plus Craftsman, 1Build, and RSMeans, so you see today&#39;s cost, not a stale allowance.</li><li><strong>Compare before you approve.</strong> Because the estimate updates live, you can hold the old number next to the new one and see the swing before signing off on the substitution.</li><li><strong>Keep a defensible trail.</strong> The updated, sourced number is what you show the owner or GC — a number you can back up, not a guess that gets argued over later.</li></ol> <p>The fix isn&#39;t catching the swap after the fact. It&#39;s making the estimate fast enough that pricing the change is part of approving it.</p>