Bloomberg has a good look at Bob Rennie, the Vancouver collector, who wants to get credit as an art investor. The story has a lot of great detail about what it takes to collect in depth and without breaking the million-dollar barrier. But one essential element is missing from Rennie’s investment claims: sales. All of Rennie’s gains are nominal and there’s no evidence he’s planning to sell at any time soon.

“We can’t pretend that art is not an asset,” Rennie said last month as he walked through the Armory Show, the largest contemporary art fair in New York. “It has to be managed.”

The founder of Rennie Marketing Systems, a real estate sales, marketing and risk management company, estimates that a third of his art holdings rise in value “astronomically.” Another third barely keeps up with bank rates, he said, and one third was purchased as an intellectual pursuit and is unlikely to rise in value. About 140 works represent 75 percent of the total value of his collection.

“At the time of the acquisition, you don’t know which one is which,” he said, referring to the three groupings.

In 2009, Rennie opened a private museum in the oldest building of Vancouver’s Chinatown district. Operating the museum and managing the collection of about 200 artists including John Baldessari, Mike Kelley and Christopher Wool costs $75,000 a month, he said. He regularly lends to public museums and has sold only five artworks in the past 10 years, he said.

Thinking of Investing in Art? This Collector Offers Rules (Bloomberg Business)