Take a tool that agencies sell for ¥100K a month, sell it to sole traders for ¥5K, then pay your three free beta users ¥5,000 a head to sell it for you — the exact sequence that took a Japanese solo dev to ¥200K/month
~¥5,000/mo price point · ~10% free-to-paid conversion · ¥100K total paid in referral bounties, recouped in 4–5 months
Fewer bars = easier, cheaper, or faster for an AI-assisted solo builder. Editorial judgments based on the case details.
This is a Japanese solo developer explaining, step by step, how he took a self-built web service from nothing to its first ¥10,000 of revenue — and he opens by saying that the same procedure, extended, is what has since grown it to ¥200,000 a month. He offers that as his claim to reproducibility, and he is careful about the limits of his own authority: he says he has no experience outside this one path, so repeating general theory or second-hand advice would be worthless, and he will only describe what he actually did. He sets one hard precondition up front, and it narrows the applicability of everything that follows. The tool has to be B2B, and specifically it has to be a B2B tool priced for people who cannot afford B2B pricing. His framing: this class of software normally sells for tens of thousands to hundreds of thousands of yen a month, and the play is to sell essentially the same capability to sole traders and one-person businesses for a few thousand yen a month. He acknowledges this immediately excludes a lot of people. His own product is an Instagram tool. The transcript never names it, never shows a dashboard, and never states the exact price — the ¥5,000 monthly figure he works his arithmetic from is presented as an example, though it is clearly close to his real number given he describes the referral bounty as roughly one month's subscription. He also runs a school that takes people from zero to a published product, which is disclosed and is the commercial reason the video exists. The monetisation playbook is where the substance is, and it is unusually specific.
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Create free accountEmail code only. No password.Data credibility: Japanese-language first-person account by a solo developer, and readers should know exactly how thin the proof is. The product is never named anywhere in the transcript — it is described only as "an Instagram tool" that he built and sells to individual business owners. No dashboard, screenshot or invoice is shown. The ¥200,000 per month figure appears in a single opening sentence, offered as evidence that the method he is about to describe is reproducible; the video also promotes a school he runs that helps people build and publish a product, which is the commercial reason it exists. The ¥5,000 monthly price point is explicitly presented as an example (「5000円というのは例えばですが」) rather than as his actual price, though he describes the referral bounty as roughly one month's subscription, which suggests it is close. The figures he states directly and consistently are: about 10 DMs a day for about a month equals 300 messages, roughly 1 reply per 100, 3 monitor users as the step-one target, ¥5,000 per referred registration, about 10% free-to-paid conversion, 20 referred users producing 2 paying customers, ¥100,000 total in bounties, a nominal 10-month payback that he says came in at 4–5 months in practice, and over ¥10,000 per acquisition for cold paid ads with no track record. We have kept every figure in yen because the transcript never converts to dollars, and we have not applied any exchange rate. Retention and churn are never mentioned, which matters because the payback claim depends on them. Where we have inferred anything — such as the implied customer count at ¥200,000 against a ¥5,000 price — we have said so explicitly in the body rather than presenting it as his number.