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How-To Guides

Practical guides for subcontractors choosing job costing software, tracking change orders, and protecting margins.

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How to Calculate WIP in Construction: The Formula and What It Means

Guide

A practical guide for specialty trade subcontractors calculating WIP (work in progress) using the percentage-of-completion method. The formula, a worked example, and what under-billing and over-billing mean for your balance sheet.

Updated Mar 20, 2026 30-90 minutes depending on job count (automated if using job costing software)

Job Costing Template for Specialty Trade Subcontractors (Free Google Sheets)

Guide

A practical job costing spreadsheet template for specialty trade subcontractors. What tabs you need, how to set up WIP calculations, and when a spreadsheet stops being enough.

Updated Mar 20, 2026

How to Estimate Construction Jobs: A Guide for Specialty Subs

Guide

A practical estimating guide for specialty trade subcontractors. How to build a complete estimate from takeoff through margin, calculate labor burden correctly, and hand the estimate off to job costing.

Updated Mar 20, 2026 2-8 hours depending on scope

Procore Is Too Expensive for Most Subcontractors — Here's What to Use Instead

Guide

Procore starts at $375/user/month and was built for general contractors. For specialty trade subs in the $1M-$20M range, there are purpose-built tools at a fraction of the cost.

Updated Mar 20, 2026

Purchase Order vs. Invoice in Construction: What Every Sub Needs to Know

Guide

A PO commits a cost before materials are delivered. An invoice is what the supplier sends after. Here's why specialty trade subs need both — and what skipping POs costs you.

Updated Mar 20, 2026

Time and Materials Contracts: What Specialty Subs Need to Know

Guide

A T&M contract pays you for actual labor hours and materials at cost plus markup. Here's how to track them accurately — and protect yourself when the GC pushes back.

Updated Mar 20, 2026

What Is Retainage in Construction? How Subs Track and Collect It

Guide

Retainage explained for specialty trade subcontractors. What it is, how it affects cash flow, how to track retainage receivable, and how to collect it when the job closes.

Updated Mar 20, 2026

Schedule of Values in Construction: What It Is and How to Build One

Guide

A schedule of values is the line-item breakdown of your contract used to calculate AIA billing. Learn how to build one that matches your cost structure and supports accurate progress billing.

Updated Mar 20, 2026

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