01STRUCTURE: it is 事業譲渡 (business transfer) or bare 資産譲渡, never 株式譲渡, because at this size the seller is a 個人事業主 or a one-man KK selling one property from a portfolio and there is no entity to buy. This is good for a first-time acquirer: hidden liabilities stay with the seller because only named assets and named contracts transfer. The one exception to guard is 会社法22条, under which taking over the seller's 商号 can make you liable for their business debts, so exclude the trade name in the contract or register an explicit 免責.
02NATIONALITY: your US citizenship creates zero Japanese acquisition restriction. Under 外為法26条1項1号 an 外国投資家 is a 非居住者である個人, a non-resident individual. You are a 居住者, so the inward-direct-investment regime does not reach you at all. No 事前届出, no 事後報告, no waiting period. The dormant KK is also not an 外国投資家 because 26条1項3号 only catches companies 50%+ owned by one.
03ENTITY: default to buying as the 個人事業主. It needs no new registration and no new filings, and it keeps the US side simple (a disregarded sole proprietorship on Schedule C with foreign tax credit relief). Two things override that default. A .co.jp target legally cannot be held by an individual (JPRS restricts it to companies registered in Japan; .jp only needs a Japanese address, which you have), and sustained profit past roughly ¥8-10M net starts favouring corporate rates. If the KK becomes the acquirer, you own a CFC: annual Form 5471, GILTI inclusions on essentially all profit because a website has no tangible asset base, and a USD 10,000 minimum penalty for a missed form. Engage a US expat CPA before deciding, and subtract their USD 1,000-3,000/year from the Japanese tax saving before comparing.
04CONSUMPTION TAX, the highest-value item on this list: essentially the entire price of a website deal is 課税資産 (goodwill, domain, content, copyright, code, member data), so plan on paying price x 1.1. Whether that 10% is recoverable depends entirely on your calculation method. On 本則課税 it is reclaimable as 仕入税額控除. On 簡易課税 or the 2割特例 it is a permanent unrecoverable cost, ¥500,000 on a ¥5M site and ¥1,000,000 on a ¥10M one. Your invoice registration T5810247107197 proves you are a 課税事業者 and says nothing about which method you are on. Switching cannot be done retroactively: the 消費税簡易課税制度選択不適用届出書 must be filed before the start of the taxable period, so for a calendar-year individual filer buying in 2027, that means by 2026-12-31, and 簡易課税 carries a two-year lock-in.
05SELLER'S INVOICE STATUS: ask every seller for their 適格請求書発行事業者 registration number before pricing. A registered seller means full input credit. An unregistered 免税事業者 seller caps your credit under the 経過措置 at 80% now, stepping down from 2026-10-01. The 令和8年度税制改正大綱 softened the taper to 80% then 70% then 50% then 30% to nil by 2031-09-30, but NTA's own page still shows the old 80/50 wording and secondary write-ups disagree on the middle years, so have the 税理士 confirm against enacted law. On a ¥10M purchase from an unregistered seller the difference between 80% and 70% is ¥100,000. Put it in the price you offer.
06THE ¥10,000,000 LINE: any single purchase at ¥10M or more tax-exclusive (roughly USD 63,000 at 159 JPY/USD) is a 高額特定資産 and locks you out of 免税事業者 status and 簡易課税 for three taxable periods. Two purchases at ¥6M each do not aggregate, because the test is per 取引の単位. That is a genuine structural argument for buying two or three cheaper properties rather than one at the ceiling, independent of the portfolio maths.
07GOODWILL AMORTISATION: 営業権 is a named 減価償却資産 at 所得税法施行令6条8号ヲ with a statutory 5-year 耐用年数 under 別表第三, using 定額法, and for an individual the deduction is compulsory rather than elective. A ¥6M site bought as goodwill gives ¥1,200,000/year of deduction for five years, prorated monthly in the first year. Because it is compulsory you cannot defer it into a higher-income later year. If the KK buys instead, the goodwill is likely 資産調整勘定 over 60 months rather than 営業権 over 5 years; same duration, different mechanism, and I could not verify the statutory basis for a plain 事業譲受け, so ask the 税理士 and do not accept an article number that has not been checked.
08STAMP DUTY: sign electronically and 印紙税 is zero. A site sale contract on paper is 第1号文書 (無体財産権の譲渡 covering 著作権 and 商号, plus 営業の譲渡) and costs ¥10,000 at ¥5-10M and ¥20,000 at ¥10-50M. Stamp duty attaches to the creation of a paper document under 印紙税法基本通達44-1, so a PDF exchanged or signed in Docusign creates no taxable document. Rakko M&A signs through Docusign at its own cost, so on that platform the question never arises.
09ESCROW: Japanese platforms run real escrow. Rakko M&A holds the purchase price (仮払い), automates deposit confirmation, refunds the buyer in full if the site fails inspection, auto-generates a lawyer-supervised contract you can edit, and provides free lawyer consultation over chat, charging the buyer 5% with a ¥55,000 tax-inclusive minimum while the seller pays nothing. SiteStock runs the same pattern with the escrow itself free. Neither platform states a legal framing (no 資金移動業 registration, no 信託 segregation, no licensed third-party agent mentioned), so these are platform-held funds relying on the platform's solvency. For anything near the ceiling, ask in writing how client funds are segregated before wiring. Never settle off-platform: a wire-transfer request outside escrow is the single most reliable fraud signal at this price point.
10BATONZ FEE WARNING: BATONZ charges a minimum buyer fee of ¥385,000 including tax on deals under ¥10M, which is a 26% surcharge on a ¥1.5M listing. Treat BATONZ as a Tier C-only channel. BATONZ 83045's true all-in cost is ¥11,000,000 including its disclosed ¥1,000,000 Lehman fee, not the ¥10,000,000 headline.
11TRANBI BLOCKER: per prior vault research TRANBI will not verify a foreign national on a residence card or passport and requires a My Number Card. TRANBI holds the largest Japanese web-media inventory, including the best structural fit in this harvest (listing 18129), so if you want that channel open, start the My Number Card application now. Treat it as blocked until it exists.
12CONTRACT: the market-standard サイト売買契約書 is a 17-clause 事業譲渡 document (譲渡対象 covering domain usage right, program, design, content, passwords, all IP, member data and contractual position; receivables and payables up to the 譲渡基準日 staying with the seller; 著作者人格権 handled by a non-exercise clause; 2-year 競業避止 from the 譲渡基準日; 6-month 瑕疵担保; 1 month of free transition support). Its 表明保証 deliberately disclaims responsibility for SEO順位 and 顧客継続, which is exactly the risk you are buying. So the leverage is structural rather than contractual: negotiate a 20-30% holdback released after 60-90 days of verified traffic and revenue, and push the 1 month of transition support to 3 months for a Japanese-language property. Refuse any earnout the seller proposes; it moves their performance risk onto you on metrics you have not yet learned to run.
13CORPORATE SELLER: if the seller is any kind of company, ask for the 株主総会議事録 or board minute authorising the sale (会社法467 requires a special shareholder resolution for a transfer of all or an important part of a business, with 略式 and 簡易 carve-outs at 468 whose numerical thresholds counsel should confirm), and keep the standard warranty that all 会社法 procedure has been completed. If the seller is a 個人事業主, the contract alone is sufficient.
14DOMAIN TRANSFER: two separate procedures, not one, and budget several days. 指定事業者変更 is a 10-step round trip through JPRS, and the AuthCode is per-domain, single-use, and expires at 23:59:59 on the 35th day after issue. 登録者変更 (changing who owns it) is a distinct procedure at the registrar. For gTLDs, ICANN's 60-day transfer lock applies after initial registration or a previous registrar transfer with no workaround, so check WHOIS last-updated before signing. Sequence: contract signed, escrow funded, seller issues AuthCode, domain and hosting move, buyer verifies the live site plus analytics access plus revenue accounts, then escrow releases. Never pay against a promise to transfer next week.
15US SIDE: as a sole proprietor, get a J/USA-6 certificate of coverage to keep 15.3% US self-employment tax off the acquired revenue, since there is no foreign tax credit relief against SE tax. This is a question for a US expat CPA rather than the Japanese 税理士, and which Japanese scheme you are enrolled in (国民年金 versus 厚生年金) affects the paperwork.
16JAPANESE INCOME TAX: acquired revenue flows into 事業所得 on the existing return. All-in marginal rate at the USD 20k/month target (roughly ¥37M/year) is 40% national plus 2.1% surtax, about 10% 住民税, and 5% 個人事業税 (Tokyo 第1種事業, after a ¥2.9M 事業主控除, paid 31 August and 30 November). That is the scale argument for the KK, and it is a scale argument rather than a day-one one.