We find overlooked problems and build focused software that gets the detail right.
Six things we hold ourselves to across every product we build and run — in how we choose them, how we ship them, and how long we stay.
We look for specific problems in niche markets where existing tools are fragmented, overpriced or simply not good enough. If buyers are willing to pay for a better answer and a focused product can do the job properly, it is worth building.
Without customers who rely on our software every day, we have no business. We talk to them constantly, build what they need rather than what looks good in a demo, and keep earning the renewal month after month.
We ship a focused first version quickly, but only after learning the workflow properly. Speed without understanding produces the wrong product; understanding without speed produces nothing. We insist on both.
Each product is run by a small, focused team that stays close to its customers and its market. They stand on shared infrastructure — billing, auth, support, hosting — so a small team can operate like a much larger one.
In niche software, the detail is the difference. Accurate data, considered design and nothing left rough — because the small things are usually why a customer chose us, and why they stay.
Honest pricing, straight answers, no dark patterns and no lock-in tricks. On the rare occasion something isn't right, we say so and fix it. This needs no more explanation — it is simply how we operate.
Your car's original build sheet by VIN or UK registration — every factory option, paint and trim code as a clean PDF in minutes. 41 manufacturers, pay per vehicle, no subscription.
Product page →
Know the company behind the number. Diligy connects filings, financials, ownership and credit data into one verified view for faster, better-informed decisions.
Product page →We are looking for people and businesses who reach the customers our products serve. Three ways to collaborate:
Recommend Buildsheet Pro or Diligy to your audience — car forums, dealers, specialists, deal teams — and earn commission on the customers you refer.
Build alongside our products or connect your platform to them. Where we can, we keep our APIs open and our roadmap shared with partners.
Guest writing, co-hosted webinars, data-led stories from our products. If your audience overlaps with ours, we should make something useful together.
SAAS21 is an independent UK software studio that designs, builds and operates niche SaaS products. We currently run Buildsheet Pro, a factory vehicle specification service, and Diligy, a company intelligence and due diligence platform.
Product questions, partnership and affiliate enquiries, press, or a niche you think we should look at. A person replies within a week.