How two founders validated a $10K MRR SaaS before writing any code

Executive overview

Most indie hackers waste months building products nobody buys. Josef and Timo took a different route: they collected a $500 payment before writing a single line of code.

Their approach — a fake landing page, a fabricated demo, and a refundable deposit offer — turned SEO traffic into paying customers before any product existed. The result: Sederai, an AI appointment-setter SaaS, now at $10K MRR with 90%+ margins.

Build nothing until someone swipes their credit card.

The validation playbook

1. Have a job first. Real business pain comes from working inside businesses — not from Reddit. Prior job experience is an advantage, not a handicap.
2. Build a fake landing page. One H1 keyword, a fabricated demo video (generated with ElevenLabs), and a calendar booking link. Nothing else.
3. Use a warm domain. An existing, already-indexed domain gets Google to rank the page within 24 hours via Search Console indexing requests.
4. Find low-competition keywords. Use Ahrefs or a free SEO tool — look for search volume with low difficulty. That keyword becomes the H1.
5. Run demo calls. Booking calls lets you qualify buyers, understand their real needs, and attempt a close in real time.
6. Use the deposit framework. Offer a 100% refundable one-time deposit (e.g. $500) for early access. Frames it as a spot reservation, not a payment for nothing. Add urgency: "Secure your spot in the first launch."
7. Go high ticket. Low prices attract low-commitment buyers. High prices filter for serious customers and validate real willingness to pay.
8. Give it time to incubate. SEO attracts high-intent buyers — people actively searching for a solution. That takes weeks, not days.

What Sederai actually is

• AI appointment-setter that follows up and qualifies leads instantly via phone.
• Targets solar, coaching, financial services — sectors with high-volume outbound sales.
• Pricing: $50/month entry; top customer pays $5,000/month.
• 38 paying customers, ~2,000 total signups; focus shifted to higher-value accounts to reduce churn.

Growth strategy

• Went fully inbound — doubled down on the SEO channel that validated the idea.
• Ranked on page one within a week of launching the real site; now ranks number one globally for their core keyword.
• Three SEO levers:
  • Free tools (e.g. sales script generator) that rank on search.
  • Comparison articles targeting competitors (e.g. "HubSpot alternatives").
  • Long-form YouTube — second-largest search engine, builds high trust before a sales call.
• Most closed customers watched at least one YouTube video before booking a demo.

Business metrics and stack

• $10K MRR (August was a slow month; prior months were higher).
• Margins: 90%+ without ads; ~80% with freelancers.
• Highest costs: OpenAI API (~$250/month), Upwork freelancers (~$500/month).
• Tech stack: TypeScript, SvelteKit, PostgreSQL (Render + Supabase), Puppeteer, OpenAI API, Netlify, Cursor.
• Business tools: Ahrefs, Webflow, Calendly, Beehive, Zapier, Plausible ($29/month analytics).

Advice for founders starting out

• Charge early — it creates commitment from both sides.
• Sell high-ticket from day one; low prices attract low-quality customers.
• Inbound via SEO and YouTube compounds over time with near-zero marginal cost.