* Then read this, all of it, except perhaps most of the exhibits: Most recent Costco annual report (10-k).
* Berkshire Hathaway annual letters, Transcripts from Berkshire annual meetings
* Great follow-up: Financial Shenanigans, Fourth Edition: How to Detect Accounting Gimmicks and Fraud in Financial Reports (Schilit, Howard, Perler, Jeremy, Engelhart, Yoni, McGraw-Hill Education)
* Absolute classic (but needs to be updated): The Intelligent Investor: The Definitive Book on Value Investing. (Graham)
* On investing in general: Margin of Safety (Seth Klarman)
* Great intro to valuation, with the caveat that modern finance and concepts like WACC may not necessarily be useful to your investing strategy: Valuation: Measuring and Managing the Value of Companies (Tim Koller, Marc Goedhart, David Wessels)
* Another classic (but needs to be updated): Security Analysis (Graham and Dodd)
I've read those in more-or-less that order, interspersed with plenty of other useful books that you'll discover depending how deep you go. The most important thing is reading 10-ks.
Never thought of reading it. Thanks for the tip. Why do you recommend it so highly?
No snark intended. His letters intended for investors are the best use of your time rather than a book someone wrote for vanity.
Graham's approach shaped Buffett's. Personally, I found The Intelligent Investor to be more clearly written than Buffett's letters. It more clearly left me with a framework for how to approach value investing.
Since one share of BRK is almost $350,000 my guess is that not a lot of people you've said that to have followed your advice.
Two that I liked and still refer to from time to time are How to Read a Financial Report by John A Tracy and Financial Statements: A Step-By-Step Guide to Understanding and Creating Financial Reports by Thomas R Ittelson.