Miami’s infamous condo canyon is almost full, thanks largely to a steady flow of cash from Latin America.

The latest survey of downtown high-rises built during the housing boom shows more than 90 percent of the condos are occupied. After Latin American investors snapped up condos at distressed prices amid a wave of bankrupt high-rises, they turned to local renters to fill them. Four years into the buying spree, vacant units have almost disappeared.

“I always encourage my clients to bring their checkbook for the first month’s rent,’’ said Lauren Popham, an agent with Jeanne Baker Realty who specializes in rental units. “There is a lot more demand than there is supply.”

The study by Miami’s Downtown Development Authority found 93 percent of the nearly 23,000 condominiums built in downtown Miami after 2002 are occupied. Of that, only about a third are occupied by full-time by owners, with the majority serving as rental apartments.

Behind the statistics are a fundamental shift in real estate math allowing for downtown Miami to become one of South Florida’s hottest rental markets.

The boom prices, where top condos were selling for $600 or more a square foot, would require rents too pricey for all but the most affluent residents. Instead, investors who bought then hoped to flip their units for even more money to future buyers.

Even at the sharply discounted $200-a-foot purchase prices in the depths of the housing bust, many of the condos would be too expensive to generate enough rent to cover association fees and mortgages on the units, said Craig Werley, of Focus Real Estate Advisors and author of the DDA study. But with the vast majority of investors paying cash for their downtown condos, they require far less rental revenue each month to make the deals “pencil out” as reasonable investments, Werley said.

“Traditional financing wouldn’t have made these rentals viable,’’ said Werley, who conducted the study in a partnership with Goodkin Consulting. “If you had a mortgage on a half-million-dollar condo, the monthly costs would be way out of line with any reasonable rent you could generate.”

Not all condos being rented in Miami’s urban core depend on cash investments, and the DDA study only covers units built during the last decade. Other indicators point to a downtown that is an increasingly popular place to be. The bust didn’t stop a wave of new retail complexes from opening, including the Midtown Miami mall on northern side of downtown and the Mary Brickell Village mall to the south. Restaurant taxes have surged 77 percent within Miami city limits since 2005 compared to a 35 percent gain countywide.

Tyler Tejeda commutes almost an hour each way in order to spend weekends in Miami. The 24-year-old recruiter for a Fort Lauderdale firm moved into a Brickell Avenue apartment in August, despite having a job nearly an hour away. “I could move to Fort Lauderdale if I really wanted to,’’ Tejeda said. “But I’d rather be in Brickell on the weekends. It bothers me less to have to commute on weekdays than have to come down to Miami on the weekends.”

Paul Riemer could afford to buy a condo of his own, but the young insurance executive instead pays upwards of $2,000 a month for a one-bedroom apartment at the Icon, a posh condo complex on Brickell Avenue.

“I’m not ready to make a big purchase yet,’’ the 23-year-old said. He cites a gap in what he can afford to rent and what he can afford to buy. Why move out of a luxury apartment to purchase his own condo somewhere else with a large mortgage?

“I have the money to comfortably rent,’’ Riemer said. “I don’t know if I’d be able to comfortably buy.”

The 93 percent occupancy rate in the latest DDA condo survey identifies little more than 1,000 vacants units in a condo market that came to symbolize the excess of Florida real estate. And it marks a big improvement over the 65 percent occupancy rate in the first DDA survey taken four years ago — a number that at the time seemed surprisingly high.

That was in 2008, at a time when South Florida real estate sales were just beginning to show a rebound. But prices were heading the other way, accelerating into a decline that has so far last five years, according to the Case-Shiller housing index. At the time, the DDA wasn’t sure it wanted to know how many people were living downtown.

“We were hearing from everybody driving down the road: Hey the condos are empty,’’ said DDA director Alyce Robertson. “You never know what the numbers are going to say. What if they really were all empty?”

With a hot rental market, downtown Miami has become a more expensive place to live. Mark McCann, owner of the Miami Apartment Locators brokerage, said a one-bedroom apartment in the downtown area went for about $1,300 a month several years ago. “Now that’s almost impossible,’’ he said. “Now it’s closer to $1,500 or $1,600. There is a lot of competition for the units. There was more supply before the recession.”

The rental market has helped usher in a new crop of condo projects downtown, a revival many thought might have to wait at least a decade after the big crash. Harvey Hernandez runs the company selling units in Brickell House, a 46-story building planned for 1300 Brickell Bay Drive. His sales staff runs weekly reports on the rental market — statistics that can help close a sale for a $400-per-square-foot unit at Brickell House.

“The rental market influences the buyer a lot. It is a great option,’’ Hernandez said. Miami “has about half the inventory available for rent we had four months ago. And four months ago, it was at least half of what it was four months prior.”