<prompt> Human: By way of background, Im a 50-something guy who grew up in a family with what could charitably be described as a generational experiment in financial mediocrity. My parents were a rambling financial disaster, and when my dad died he passed away deeply in debt. My grandparents frequently had to pitch in just to keep the lights on in my house.So, I began my adult life with no great financial role models but my experience did instill in me a desire to become financially secure. But, like most people I made a lot of mistakes in my 20s and 30s, eventually got my shit together in my 40s, and in my 50s I have a relatively high net worth, little debt, and a financial plan to carry me through the rest of my life.I dont pretend that my experiences will be your experiences or that Ive arrived at financial enlightenment. My hope in posting this is that perhaps a few people can learn from my many mistakes and few triumphs and get a little ahead of the learning curve. Its the kind of post I wish someone had handed to me in my 20s.Here are five lessons Ive learned:1. It is easier to increase your income than radically cut expenses. Im not suggesting that frugality doesnt have its place, but in terms of increasing your lifetime net worth your time is better spent increasing the market value of your professional skills than in squeezing every dime. If youre not learning a significant number of new and marketable skills every year of your professional life then youre not going to maximize your income. At a minimum you should be reading a half dozen books a year that increase your marketable knowledge. This knowledge base should be coupled with an attitude of situational awareness in which you are always looking for new opportunities and you have the willingness to exploit them. This is the formula that produces the luck that creates wealth.2. Experiences have far more value than material items. There is literally not a single material item that I purchased in my 20s and 30s that holds any value for me two decades later. Sure, I had to have a car and food at the time, and they filled a need at that moment. But, in terms of things I remember with fondness, all revolve around doing something and not owning something. While youre young and your body is at its peak go out in the world and live. You can always buy that cool watch when youre old.3. Never buy a depreciating asset with debt. This includes meals, clothes, cars, and vacations. When you buy a depreciating asset with debt, essentially you pay for it twice: once when you buy it, and again when you pay interest on it. If this means only buying a shitty car then buy a shitty car. A shitty car today will put you in a much nicer debt-free car in a few years.4. Live below your means. As a general rule, plan on living month to month on 12 your income. The other half should be used to pay taxes and save for your retirement. You need to cultivate a mindset that enough is enough and create a mental thermostat that cuts off spending when youve achieved some reasonable semblance of comfort. A small house that is well designed can be more beautiful than a McMansion monstrosity. Do not get sucked into the vortex of striving for social validation by competing with your peers on a material level. The expensive neighborhoods of America are full of people who put on an opulent front but are desperately living large paycheck to large paycheck, trying to juggle the BMW lease payment with the expense of 40 a bottle wine. Avoid this trap.5. Question conventional investment advice. I have found professional investment advisors to be sorely lacking in their ability to consistently beat the stock market, and I have found the stock market in whole to be a poor place to make money if you dont work on Wall Street. I closely analyzed the major asset categories available to the average investor and took an entirely different route. Im glad I did. Assistant: Do you have any suggested reading materials? 23 year old college student here.Human: Id suggest you read The Millionaire Next Door and some biographies of people who built wealth. I read lots of investing and personal finance books once I hit my stride on the earnings side. At first I did what they all suggest: diversifying your portfolio between stocks, bonds, cash equivalents, with a smattering of precious metals, etc. I tried that for about five years, got my ass kicked, then quit doing it.I then built some spreadsheets and relying on historical data made basic assumptions about all major asset classes: stocks, bonds, real estate, etc. Despite my initial bias to the contrary, when I gamed it out commercial real estate kept throwing off the best return in my simulations. So, I read everything I could on the subject and talked to real estate guys. I remember one book entitled like Never Sell or something like that. For whatever reason this clicked with me. Also, kind of at random, I was reading the obituaries in the New York Times one day, and came upon the story of a guy who died owning 99 little commercial properties that he had amassed over a lifetime. He started with nothing and methodically built a 100 million real estate portfolio.I started small. The first building I bought held a local bagel shop and cost in the 400,000 range. I put down 20 to buy it thats the industry standard, by the way. I paid it off a long time ago, and today its worth about 600,000 and throws off 4,000 a month in rent. I now have about ten other properties, too. On the average I buy about one every two years or so. Ill scan hundreds of listings to find one worth buying, but Ive taught myself the relevant criteria to look for and the search actually requires very little time or effort.  <response>: relying on historical data made basic assumptions about all major asset classes: stocks, bonds, real estate, etc.I guess Ill chime in and say, past performance is not indicative of future results. 