Contract modifications are where most SaaS and services companies quietly accumulate accounting errors. Here's the classic SUMPRODUCT approach and the one-formula 365 SCAN fix that auto-classifies modifications and calculates cumulative catch-up — plus a free workbook blueprint.
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Most amortization tables are a fragile ladder of copy-down formulas that shatter the moment you insert a row. Here's the classic PMT/IPMT/PPMT build, and the Excel 365 dynamic-array version that spills the whole schedule from a single cell — plus a free workbook.
Excel's NPV function quietly assumes your first cash flow lands one full period in the future — so it discounts the whole project by an extra period and hands you a number that's off by thousands. Here's the classic fix, the XNPV/XIRR way for real dates, plus a free workbook.
Standard Data Validation dropdowns have no idea what's already been chosen elsewhere — which is exactly how the same meeting room, laptop or seat ends up double-booked. Here's the classic OFFSET trick and the one-formula 365 FILTER fix, plus a free workbook.
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