Some say you get what you pay for.  That’s not true with Warren Buffett.  He’s been dishing investing wisdom for decades, and his advice is both free and priceless. He’s living proof that price is what you pay, value is what you get.

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His annual letters to Berkshire Hathaway shareholders house his best advice.  The collection of letters should be the first thing any new investor reads.  As a shareholder, I study his letters every year.

He repeats himself.  The same themes crop up in his letters year after year.  I suppose he’ll continue to repeat himself until investors finally listen.

Here are 4 lessons Warren Buffett teaches that every investor should learn:

1.  Stock repurchases:  Companies often repurchase shares at the expense of shareholders.  Management has a knack for buying back shares at inflated prices.  The cynic in me assumes management is trying to increase the price of a share to goose the value of its options.  Just as likely, though, management is as bad as most everybody else at investing.  The letters ‘CEO’ affixed to a name does not a Buffett make.

Here, Warren Buffett leads by example:

As I’ve long told you, Berkshire’s intrinsic value far exceeds its book value. Moreover, the difference has widened considerably in recent years. That’s why our 2012 decision to authorize the repurchase of shares at 120% of book value made sense. Purchases at that level benefit continuing shareholders because per-share intrinsic value exceeds that percentage of book value by a meaningful amount. We did not purchase shares during 2013, however, because the stock price did not descend to the 120% level. If it does, we will be aggressive.

Clear. Concise. Consistent.  CEOs and investors alike would do well to follow his example.

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2. You invest in businesses, not stocks:  Imagine you wanted to buy a real live honest to goodness business.  You learn that a local business, say a gas station, is for sale for $1 million.  Without knowing more, would you buy it?  Of course not.  You’d want to understand its revenue, expenses, growth potential, assets, liabilities, and a host of other information.

Yet when it comes to stocks, many investors “play the market” knowing very little about the businesses they are buying.  Rather than focus on the underlying business, we are all too often consumed with market quotations.

Warren Buffett takes a different approach:

With my two small investments [referring to two properties he had purchased], I thought only of what the properties would produce and cared not at all about their daily valuations. Games are won by players who focus on the playing field – not by those whose eyes are glued to the scoreboard. If you can enjoy Saturdays and Sundays without looking at stock prices, give it a try on weekdays.

3.  Focus on per share results:  Throughout his letter to shareholders, Warren Buffett focuses on per share results.  He compares the growth in Berkshire’s book value per-share to the performance of the S&P 500.  Warren Buffett explained his “goal of not simply growing, but rather increasing per-share results.”  And he described how he would achieve that goal:

With this tailwind working for us, Charlie and I hope to build Berkshire’s per-share intrinsic value by (1) constantly improving the basic earning power of our many subsidiaries; (2) further increasing their earnings through bolt-on acquisitions; (3) benefiting from the growth of our investees; (4) repurchasing Berkshire shares when they are available at a meaningful discount from intrinsic value; and (5) making an occasional large acquisition. We will also try to maximize results for you by rarely, if ever, issuing Berkshire shares.

Dilution matters.  A company that grows earnings in the aggregate, but reduces them through dilution on a per share basis, proves the axiom–A rising tide sinks all boats.

4.  Bull markets are fun, until they’re not: For those enjoying the recent rise in the market, Warren Buffett teaches like only he can:  ”Remember the late Barton Biggs’ observation: ‘A bull market is like sex. It feels best just before it ends.’”