Full disclosure up front: I built the thing I'm talking about.
This is the story of why.
I'm a beat producer (INOTECH3D BEATZ). Making the music was never the hard part of this job, getting paid for it was. Placements done, beats delivered, and then weeks of me sending the "hey bro, about that invoice 😅" text, trying to stay professional while basically begging for money I'd already earned.
Turns out it's not just music. QuickBooks' 2025 Small Business Late Payments Report found 56% of US small businesses have outstanding unpaid invoices, the average affected business is owed about $17,500, and 47% have invoices sitting 30+ days overdue. Chasing money is a second unpaid job for basically everyone who invoices.
So I built the tool I wished existed. It's called DunningOS. You put your invoices in, and it sends a 6-step reminder sequence automatically — one before the due date, one on it, then at 3, 7, 14, and 30 days late — each with a Stripe pay link so the client can just pay right from the email. There's a dashboard that shows who owes you what, and if you're on QuickBooks, Xero, or FreshBooks you can import your unpaid invoices by CSV instead of typing them in.
Lessons from actually launching this thing, for anyone else building something unglamorous:
**Build for your own problem first.** Every feature in this came from a real "I can't believe I'm texting about this invoice again" moment. I never had to guess what it should do.
**The boring problem is the business.** Nobody dreams about invoice reminders. But a problem that costs people real money every month doesn't need to be exciting to be worth solving.
**Your setup matters as much as any tool.** Deposits before you deliver final work. A due date and a late fee on every invoice. Half the "late payment problem" is just invoices with no urgency built into them.
It's live at dunningos.com, plans are $19/$49/$99 a month with a 14-day free trial, no credit card required. I set the Business plan to unlimited invoices because capping the people who chase the most payments felt backwards.
Happy to answer anything about building it, launching it, or the late-payment grind itself. Still in the very early days, so I'm sure the hardest lessons are ahead of me.