EstiMate: Multi-Tenant SaaS Estimation Platform for Contractors
Joey Musselman · January 15, 2026
Blue-collar service contractors — painters, electricians, plumbers, landscapers — run their estimation process on spreadsheets, Word docs, or handwritten notes. Every bid requires manually calculating labor, travel, permits, equipment rental, and project management costs. Estimates take hours and pricing errors cost real money. The cheapest competitor tools start at $39/month and are bloated field service platforms that include scheduling, GPS tracking, and features contractors don't need.
Challenge
Build a focused estimation tool that supports multiple industries out of the box, isolates each business's data completely, and is simple enough that a contractor can start creating professional estimates in minutes. The platform needed industry-specific templates with realistic pricing, a multi-stage approval workflow, and complete multi-tenancy so each organization's data stays private.
My Role & Contribution
Sole Developer — Full-Stack Design, Development & Deployment
- Architected a multi-tenant SaaS platform with complete data isolation per organization using Supabase Row Level Security and Prisma ORM
- Built onboarding flow supporting 8 industries (warehouse, painting, software, construction, electrical, plumbing, landscaping, other) with auto-seeded project types and templates
- Created 3 fully seeded demo verticals (warehouse, painting, software) with 5 templates and 3 sample estimates each, plus dedicated demo accounts
- Designed a 5-stage workflow (draft → review → sent → accepted/rejected) with categorized line items across labor, travel, permits, equipment, and project management
- Implemented search, filtering, estimate duplication, and print/PDF export for client-facing delivery
- Deployed to production on Vercel with Supabase PostgreSQL backend and Supabase SSR authentication
Key Technologies
Impact
Live in production at estimate.joeymusselman.com serving multiple demo tenants. Positioned in an underserved market gap — no estimation-only tools exist below Jobber's $39/month, and Jobber is a full field service management platform. EstiMate targets the 1-5 person contractor shops that need professional estimates without the bloat, at a fraction of the cost.
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