From bid to invoice — all in one system
The situation before we started
The company had expanded from residential remodels to commercial fit-outs, and with that growth came complexity they weren't equipped to handle. Fifteen active projects meant fifteen Excel files, each owned by a different PM, each formatted differently. Budget overruns were discovered after the fact. Subcontractor invoices arrived by WhatsApp photo. The finance team spent the first two weeks of every month reconstructing what had actually been spent before they could issue client invoices — by which point cash flow was strained. The owner had looked at Procore and Buildertrend but found them too bloated and too expensive for their team size.
What made this hard
They needed a system where project managers could track bids, assign tasks, monitor material costs, log daily progress, and trigger invoicing — without a separate tool for each function.
Bid data from estimating had to flow into project budgets without re-entry
Field workers needed a simple mobile view to log daily progress and material use — they weren't technical
Subcontractor costs arrived as photos of handwritten invoices — needed a structured way to capture and approve these
Project budget vs. actual had to be visible in real time, not at month-end
Client invoices needed to be generated from actual logged costs and sent with one click
How we built it
Phase 1 — Module Design & Data Model (Weeks 1–2)
Ran workshops with the owner, two PMs, and the finance lead to map every workflow from bid to invoice. Designed a data model that linked bids → projects → tasks → costs → invoices without requiring data re-entry at each stage.
Phase 2 — Bid & Project Core (Weeks 3–7)
Built the bid module (line items, material costs, labour estimates, margin), and the project management module (phases, tasks, assignments, status tracking). Implemented budget vs. actual tracking that updated in real time as costs were logged.
Phase 3 — Field Worker Mobile View (Weeks 8–10)
Built a simplified responsive view for field workers: they see their assigned tasks for the day, can log hours worked, record materials used, and upload site photos. Designed to work on slow mobile connections with local-first caching.
Phase 4 — Invoicing & Reporting (Weeks 11–14)
Built the invoicing engine: invoice generated from logged costs, formatted as a branded PDF, sent directly to the client from the platform. Added project-level P&L reports and a cross-project dashboard for the owner.
Features shipped
How it's built
Next.js frontend with server-side rendering for the reporting dashboard. Node.js API layer with PostgreSQL. PDF generation using a headless PDF renderer with branded templates. Responsive mobile UI for field workers using progressive web app patterns with service worker caching for low-connectivity scenarios. Hosted on AWS with S3 for document and photo storage.
What changed after launch
Get the full case study as a PDF
Includes detailed architecture diagrams and implementation notes — free to download.
Ready to build something
that actually works?
Book a 30-minute strategy call. No sales pitch — just an honest conversation about your project and the best way to approach it.
30-min call · No commitment · Response within 24 hours