Most founders budget only for the developer. That is not the total cost. There are costs before the build, costs during the build, and costs after launch that nobody mentions until you are already paying them. Here is the real breakdown.
Before the Build
Validation: $0 to $500. Landing page tests, user interviews, competitive research. This costs time, not money. But skipping it is the most expensive mistake a founder can make. Building the wrong product costs three to five times more than building the right one.
Design: $0 to $2,000. Some developers include basic design in their price. Others charge separately. If you have a designer on your team, this is free. If not, budget for it.
Real MVP Cost Breakdown - First 3 Months (USD)
Development is visible. Opportunity cost and marketing are the two most underestimated line items.
During the Build
Development with a fixed-scope specialist runs $5K for a focused first product. That covers authentication, payments, core features, and deployment with no surprises on the final invoice.
Tools and services: $0 to $100 per month. Supabase (free tier), Vercel (free tier), an error tracker (free tier), Resend (free 100 emails). Your first three months of infrastructure can cost zero dollars. Paid tiers start when you cross 500 to 1,000 users, at which point you have revenue to cover them.
Build approach comparison: agency ($8,000 to $15,000) is the most expensive option with the fastest handoff. Freelancer ($5K to $10,000) requires more of your project management time. Fixed-price specialist gives you predictable scope, timeline, and cost. No-code ($0 to $500 build cost, $200 to $500 per month ongoing) looks cheap upfront but costs more over 12 months due to platform fees and the inevitable rebuild.
After Launch
Marketing: $0 to $2,000 per month. Content, ads, community participation. This is where most founders underinvest. A great product with no marketing is a hobby, not a business.
Maintenance: $0 to $500 per month. Bug fixes, feature requests, infrastructure updates. If your MVP was built well, this is low. If it was built fast with shortcuts, this is high.
The Hidden Costs Nobody Mentions
Your time: founders spend 10 to 20 hours per week on a product launch. That is time not spent on sales, fundraising, or other projects. Factor it in.
Opportunity cost: every month spent building is a month not spent earning. If your freelance rate is $100 per hour and you spend three months building instead of earning, that is $12,000 in opportunity cost on top of the development cost.
The Real Number
For a solo founder building a B2B SaaS MVP with a developer, the realistic total cost for the first three months is $7,000 to $18,000. That includes development, tools, basic marketing, and your time. Plan for that range, not just the development fee.