Real Estate by the Numbers

Designed by a working landlord — a US Certified Public Accountant who holds the CCIM designation, with over ten years of rental operations.
　
In real estate, one bad decision costs tens of millions of yen. Here you can get it wrong as often as you like, for the price of one book, learned by playing rather than reading.
　
No characters, no gacha, no ads, nothing more to buy.
You start in January 2020 with only cash, pick a run of 5 to 30 years, and finish on net worth.
Two AI investors want the same listings.
　
　
■ What a month looks like
　
1. Read the listing — price, gross yield, cap rate, gap to market
2. Look inside — income, depreciation, cost-approach value
3. Choose the financing — five lenders, five sets of terms
4. Buy, or walk away — first-come or sealed-bid
5. Move on — rent, repayment, repairs, tax
　
Most months you buy nothing. That is a decision too.
　
　
■ Decide by the numbers, not by feel
　
- IRR — the annual rate over your hold, including the sale
- CCR — annual cash left over, against your equity
- FCR — what the property earns without debt
- K% — annual debt service, against the loan
- DSCR — how far rent covers the payment
　
When CCR > FCR > K%, debt works for you.
When that order breaks, the return on your own money falls — negative leverage.
Gross yield alone never shows the break.
　
　
■ The bank is the real opponent
　
- City bank — cheapest, lends only half the price
- Regional bank — balanced on rate, term, LTV
- Credit union — high LTV, shorter term
- Non-bank — near-full loans, longest term, highest rate
- Developer-tied — loose underwriting, costs in the price
　
Outbid a rival and your cap rate drops, your K% rises, and the bank walks away.
　
　
■ Where you buy decides where you end up
　
- Central Tokyo — rent grows 4% a year, but cap rates are barely 3%
- Rural — near 9% yields, but rent falls 1-2% every year
- Okinawa — prices and rent both climb, but salt and typhoons make repairs heavy
　
■ The numbers cannot be fudged
　
Cash flow statement, income statement and balance sheet close every month across the whole portfolio, following the practitioner's cash flow tree: GPI to EGI to NOI to before-tax to after-tax.
Profit rising while cash falls is what depreciation running out looks like.
　
　
■ Buying is not the only move
　
- Renovate — value rises only if ROI beats the cap rate
- Build from land — no rent while building, and one in three runs late
- Sell — market price is current NOI over cap rate
　
Policy rates reset every January, and every 8-11 years something breaks.
It usually lands mid-build, and payments never pause.
Run out of cash and you go under; profitable on paper is not enough.
　
　
■ Built for people starting out
　
Nineteen chapters and a glossary are built in, reachable from the ? in the corner, and every term is spelled out before it is used.
Starting equity runs from 10 to 100 million yen.
　
　
■ Why this exists
　
The developer's background is corporate advisory — M&A due diligence, corporate strategy, and