“What do you think of this painting?” he asked me. “They want $250,000 for it.”

SP is a former protégé and current partner. He’s had a very successful career. He’s got a beautiful house and lots of expensive toys, but he doesn’t spend money foolishly. So it didn’t surprise me that if he was going to venture into buying fine art, he’d ask one of the few people he knew that had some experience.

The image was well done but conventional. I was only vaguely familiar with the artist. But since I knew the broker, I was pretty sure the piece was being offered at an aggressive price. So I looked up the recent history of the artist’s pieces sold at auction and saw that the painting my colleague was interested in was, indeed, seriously overpriced. I told him so. He didn’t buy it.

He sent me a note, expressing consternation at the process of buying investment-grade art. “It’s not like stocks and bonds,” he observed. “There is no transparency.”

That is partly true. If you are buying art from a dealer, you may find yourself relying exclusively on the information he provides. This gives an unscrupulous dealer, knowing how little most buyers know about art, a big advantage. Art brokers, though, usually won’t lie. It could get them in trouble. But they can and will select the facts they want to convey and omit those they would rather not divulge.

When I first went into the art business in 1989, the retail buyer was greatly dependent on the honesty and integrity of his dealer. Although there were records of auction sales, they were published in large bound volumes months after the auctions took place. Hardly anyone but art dealers and auctioneers even knew they existed.

I used those books then and they taught me a lot. Among other things, they taught me that once you understood some basic facts about valuing art, researching past sales for a particular artist could give you a very good idea of what a piece from that artist was worth.

Today, you can find just about everything you need to know about prices online. Which means you can figure out whether a particular piece is worth the asking price by doing your own research.

If you have read any of my essays on art collecting, you know that my first rule is to start small. And by small, I mean two things:

Buy just one or two artists. If you are like most people, you’ll want to buy dozens of different paintings from different periods from different artists. This is not a good idea if your goal is to become a serious collector. Buying and selling art competently requires a fair (not crazy, but fair) amount of knowledge about that particular artist. You need to know what medium he is best known for, what period is considered his strongest, what images are favored. You also need to develop an eye for the details of his work so you can spot possible fakes. You can do this in a matter of months if you focus on a single artist. Maybe two. But if you begin with a collection of a dozen or so, it will take a long time to come up to speed. And during that time, you will likely be making many costly mistakes.

Spend small. Even if you have millions sitting around with nothing to do, don’t begin by spending six and seven figures. I often advise new collectors to spend a year or two building a “baby collection.” Buying a few dozen pieces of a few dozen artists but never spending too much money on any single piece. The less you spend, in fact, the better. Why? Because I can tell you with almost 100% certainty that several years after assembling your baby collection, you’ll grow tired of it and want to start over.

That’s all good. Because the idea of the baby collection is to teach you how to buy and sell art, not to actually begin your collection. The money you are spending on those initial purchases should be viewed as tuition. You’ll learn just as much spending $50 on each piece as you would $50,000 – so why not spend less?

After you have graduated from your baby collection, it’s time to start to think about building a serious collection that will appreciate in value over time.

Start, as I suggested, with one artist. Pick an artist whose work you like and can afford. Pick one that is established – i.e., his works are part of the permanent collections of several large museums.

Most artists work in two or three media – oil, watercolor, gouache, pen and ink, and pencil. Typically, oils are more expensive than watercolors and gouaches are more expensive than pen and ink and pencil sketches tend to be the least expensive. Also, larger pieces usually cost more than smaller one.

But those are general rules. Superseding them is the quality of the image (how well rendered it is) and the type of image or period it represents. (If the artist is best known for his abstract paintings, a realistic piece will be worthless.)

For variety and to improve your knowledge you might buy one or two oil paintings, a gouache, and a pencil sketch from one artist before you move to the next.

And when you do move to the next, it’s preferable to stay close to the first artist – that is, to buy another artist from the same period or the same school. This is not a hard and fast rule, but it will reduce your learning time and possible mistakes because the guidelines that apply to one artist of a school usually apply to another.

Good art comes in all price ranges. Buying expensive, museum-quality pieces does not make you cultivated. Having a sophisticated appetite for art does. It is much more impressive to see a roomful of beautiful and unusual works by unknown artists that someone has collected over the years for pennies than it is to walk into a million-dollar living room filled with very expensive junk that has been sold and bought for prestige.

Another important point: Buy unique pieces instead of prints. Prints are like condos – they do well in good markets but tend to collapse in weak ones. It’s always better, both from a personal standpoint and from an investment point of view, to have unique, original pieces that no one else has.

The most important thing is to buy pieces you like, keeping in mind that your taste will change – and improve – as you gain experience.

As time passes, you will become an expert on the artist(s) or genre you have chosen to specialize in. You will know as much about the value of individual pieces as anyone else in the world.