SAN FRANCISCO — The more things change, the more they stay the same, as the old saw goes.

The saying often holds true at the San Francisco Wholesale Produce Market.

Generations of Northern California produce families are evident at North Bay Produce Inc. and at What A Tomato Produce Co. Inc.

At North Bay, Gary Camarda and his brother, David, carry on in the industry 41 years after their father launched the company. Their sons and a daughter also contribute.

As the company name implies, the firm was first based at various locations across the bay in Marin County. It was in the early 1990s that North Bay became a tenant at the San Francisco Wholesale Produce Market, said Gary Camarda.

“At that time, we were just a distributor,” he said.

In recent years, the demand for premium quality fruit dictated expanding to a wholesale street operation, Camarda said. It was a move that quickly dictated yet another change.

“It got so we couldn’t move in the place,” he said. “It was a nightmare.”

The solution was the availability of another site within the Wholesale Produce Market. In something of a departure from the market’s tradition, North Bay operates at two locations, one for the distributing business and one for street sales.

The two site approach has proved to be a wise move.

“While deliveries are down slightly due to the recession,” Camarda said, “our street business has more than doubled.”

The recession has been something of a rough patch, too, for What A Tomato, said owner Bob Pizza, whose family also dates back a few decades at the market.

It has not prevented him from considering expanding the company’s inventory to include other vegetables and potatoes, he said.

California’s water woes have reduced the number of his suppliers, Pizza said.

“There’s a big trust issue. Consistency is a big thing,” he said.

To provide only top quality fruit and to satisfy his customers, Camarda is finicky about his suppliers. It is all about relationships, he said.

“You know what I’m looking for,” he said he tells the growers. “Don’t send me something else.”

North Bay’s suppliers are sometimes headquartered in regions not well known as great fruit growing centers. While some of the company’s premium stone fruit comes from top growers in the San Joaquin Valley, other suppliers are based in Idaho and in California’s gold country. The reason, Camarda said, is the consistently high quality.

The recession also has made the industry more competitive.

“Nothing is worth less this year than at this time last year except for food,” Camarda said.

As important as the quality of the produce they market, Camarda and Pizza said, is the quality of employees. Both men have right hands that they describe as irreplaceable.

For Pizza, the right hand is in the person of Rusty Tarpley, president of What A Tomato.

“He knows the industry, he knows the suppliers, he knows the customers and what they want,” Pizza said.

Their relationship dates back well before What A Tomato was founded in 1985. Both were once employees of another produce company.

“I told Rusty back then that if I ever started my own company, my first call would be to him — and it was,” Pizza said.

Camarda lured right hand man Mike Crosby from a competitor.