How I validated my startup idea (before spending a single euro on development)

1. What you’ll learn in this post (Table of content)

• How we went from idea to proof without a dev team
• What “validation” really means (and what it doesn’t) - see also research vs validation
• The exact steps we used to test demand
• The 6 key checks to validate any startup idea
• Why building an app comes after users show interest
• How you can test your idea this week

2. The Real Story - How we avoided a €10K mistake

It was just an idea. A marketplace for parents to exchange baby and kid stuff their children had outgrown. Simple. Obvious. Tons of unused things collecting dust in closets.

We thought:

“How has no one built this in our country?”

“Let’s just build it ourselves.”

So we started talking to agencies. And that’s when we hit the wall.

The €150,000 shock

The first quote we got was €150,000. We laughed. Then panicked.

We kept going. €80K. €30K. Eventually: €10,000 from a small local dev shop.

Even that felt like too much. We were first-time founders, no tech background, no validation, no guarantee this thing would work. It just didn’t feel right to drop €10K on a hunch.

So we hit pause

We asked ourselves the question that changed everything:

“What if we don’t build anything yet?”

“What if we just ask people first?”

So we created a survey. No ads. No money spent. Just hustle: parents, friends, Facebook groups.

In 2 weeks, we had 250 responses. And 67% said they’d use a platform like this.

So now we knew: ok, looks like there's real interest...

We took that data and got specific

We asked what people loved, what they hated about second-hand groups, and what made them hesitate.

We used that data to define exactly what the platform needed:

• No fluff
• Real user pain points
• Just the features they cared about

But we still had no DEVs

We had no agency. No money to burn. Just time and belief. So we found Bubble.

And we decided to build it ourselves.

It took us almost 2 years…

Evenings. Weekends. Just Bubble, coffee, and stubbornness.

We tested. Iterated. Talked to users. Tweaked again. And again.

Eventually - it worked. The platform took off.

And then something unexpected happened…

Then something unexpected happened

Other founders started asking:

“Can you build our app like that?”

One project turned into two. Two into five. And suddenly, we had a no-code agency.

From validating a parenting platform → To building MVPs for founders → To helping startups avoid the same expensive, time-sucking mistakes.

Your takeaway

Don’t build blindly. Don’t spend €10K just to “see what happens.” If we hadn’t stopped to validate, we probably would’ve blown our budget, burned out, and never launched. But now? We help founders skip that pain and get to market 10x faster.Start small. Talk to people. Then build something they’ll actually use. Then build smart.

How to validate an idea pre-building

3. How to validate without writing a single line of code

You've heard my story. But if you're the kind of founder who likes to go deeper and work from frameworks, not just gut - read bellow. We did it, so we are sharing how we made it work.

Where startups fail? According to CB Insights, 42% of startups fail because there’s no market need. Not because of bad tech. Not because of marketing. Simply because no one actually wanted the thing.

That’s avoidable.

3.1 What “Validation” actually means

Validation = real-world signal that users care enough to act.

That action might be:

✅ Joining a waitlist ✅ Filling out a survey ✅ Booking a call ✅ Paying (even €1) ✅ Sharing it with a friend

Validation is NOT:

• Building a full product
• Posting on social media and getting likes
• Asking your mom if it’s a good idea

3.2. Why you don’t really need code to validate

Here’s what founders need to know in order to validate idea - before any code is written:

✅ Who your user is ✅ What problem they care about ✅ What messaging resonates ✅ What features they’ll pay for ✅ Whether you’re even solving the right problem

What you want to achieve here:

• Talk to potential users
• Ask them about their problems, not your product
• Look for patterns in how they’re solving it now
• Offer your idea as a “What if?” and watch their response

And how you should do it:

• Coming soon/ Waitlist / Landing page (Bubble)
• UI Prototype (Bubble)
• Survey (Typeform)
• Email outreach
• Social DMS

3.3. The fastest validation stack (we use this all the time)

1. Landing Page

• Clear problem → value → CTA
• Built in Bubble
• Add email capture or Calendly

2. Survey Trigger

• Simple 3-5 questions
• Optional reward (“Early access”, “Founder’s deal”)

3. Targeted Promotion

• Post in Reddit, LinkedIn, X...
• Email or DM ideal users
• Track clicks, signups, replies

If people take action? You’re onto something.

❌ If they ghost? Good news - you just saved €10K and 3 months. Time to move to new idea - I bet you have at least 3 more...?

3.4 Your action plan (you can do this in 1 week)

1. Define your 1-sentence problem
2. Go to where your audience hangs out (online or offline)
3. Have 10 conversations using the interview method
4. Look for strong signals of pain + willingness to pay
5. Create a landing page with email capture
6. Promote it to 1-2 niche communities
7. See who signs up. Track everything.

“If you can’t find 10 people who care, you don’t have a business. You have a hobby.”

- Rob Fitzpatrick, Author of The Mom Test

3.5 Bonus: The 10-person interview method

This is one of the leanest, most honest ways to actually test demand. It’s how hundreds of successful founders are doing it.

Here’s how it works:

1. Find where your target audience spends time and join them (Seminars, City spots, Facebook groups, Reddit, LinkedIn).
2. Ask: “Anyone here frustrated with [your problem]?”
3. Book 10 quick 15-minute calls, and offer free value in return (like lifetime deal, or couple of units FOC)

Ask questions like:

• What’s the hardest part about [your problem]?
• How are you dealing with it today?
• What sucks about that?
• Would you pay for a better way?

Pro Tip: Focus on past behavior. If they’ve tried to solve it before, the pain is real.

What to look for in their response:

1. People complain about the problem in public (forums, reviews, social)
2. They’ve already paid for solutions (even if they suck)
3. They’ve created workarounds (spreadsheets, duct-taped tools)
4. When you present your idea casually, they say:

“That would actually help me.”

“Can you let me know when that’s live?”

“I’d pay for that.”

If you’re getting reactions like this you’re on the right track. If you're not... pause and go back to drawing board.

4. Are you ready? Test with 6-point idea validation checklist

Are you there yet? Let's double check how close to validation you are:

1. You can clearly define the problem in one sentence
2. You've built landing page to test email opt-ins
3. You’ve talked to 10+ potential users (not just friends)
4. They’ve expressed real pain or hacked together solutions
5. You’ve tested messaging or concepts online and tracked reactions
6. You’ve collected at least 10 emails or DMs from interested users
7. You’ve had someone say: “I’d pay for this” or “Tell me when it’s live”

✅ 5+ points = You’re ready to build ⚠️ 2-5 points = Keep testing ❌ 0-1 = Start over (or pivot fast)

5. Need help validating your Idea?

We help founders design high-converting validation stacks. Landing pages, surveys, waitlists, and more - built in Bubble and customized to your idea.

👉 Use our Landing Page Template to launch in a day → Get the template here  👉 Or let us build it for you (takes < 1 week) → Book a free call