A renovated triplex penthouse in an Emery Roth building boasts views of Central Park from the living room, dining room, and four of six bedrooms. It has a rooftop terrace with more than 5,000 feet of outdoor space. Its price tag: $19.5 million.

The asking price of the Fifth Avenue condominium would raise few eyebrows – and might even be considered a deal – were it situated in the 60s or 70s. But this apartment, located at 1200 Fifth Ave. at 101st Street, is testing psychological boundaries. If the next bid comes close to the asking price offer that fell through over the weekend, the unit will be, far and away, the most expensive Manhattan apartment to sell north of 96th Street, real estate brokers say.

That’s because those in the market for mega-million Manhattan homes have long resisted moving north of 96th Street, a vice president and managing director of Brown Harris Stevens, Kathy Sloane, said. “It’s the first time people have contemplated purchases over $10 million in those buildings, but it will happen because of the quality of the building, and the scarcity of good real estate with park views. Lots of families are going to move in, and others are going to say, ‘Why didn’t I do that?'”

Ms. Sloane, the agent selling a 10-room, $14.6 million apartment at 1165 Fifth Ave. near 98th Street, said it is a challenge to sell such expensive apartments so far north. Safety concerns are the most common hurdle, she said. “People are going to buy when they realize the neighborhood is safe,” she said. “It’s a very good value, and people will be persuaded.”

Ultimately, the woman who made the $19.5 million bid at 1200 Fifth Ave. was not persuaded. “In the end, she didn’t want to go up to 101st Street,” the real estate agent who was brokering the deal, Carrie Chaing, said. “I know there’s nothing out there that’s comparable, and I hope to bring her back.”

Ms. Chaing is a senior vice president of Corcoran Group Real Estate, the development’s exclusive marketing agent. About a third of the building’s 32 apartments have sold, she said. Although she would not confirm the selling price of the units, the asking prices of non-penthouse apartments at 1200 Fifth Ave. range from $767,000 for a 600-square-foot studio on the ground floor to $6.6 million for a five-bedroom, five-bathroom, 3,700-square-foot apartment with panoramic exposures.

To date, the priciest Manhattan apartment at or above 96th Street – a 10-room apartment at 8 E. 96th St. – sold earlier this year for $7.25 million, according to an executive vice president of Prudential Douglas Elliman, Tamir Shemesh. An apartment at 1158 Fifth Ave. was taken off the market last summer after it failed to fetch its $11.5 million asking price, Mr. Shemesh said. “It’s very high,” he said of the $19.5 million triplex, and a $14.5 million duplex in the same building. “It’s the first time we’re seeing these kind of prices in this area.”

Still, he estimated that the same properties, located 20 blocks south, would fetch millions more. Case in point: the former Stanhope Hotel at Fifth Avenue at 81st Street, where a condominium only slightly bigger than the Emery Roth triplex is on the market for $47.5 million.

A senior vice president of Prudential Douglas Elliman, Corinne Pulitzer, said the penthouses at 1200 Fifth Ave. could very well fetch their asking prices. “It’s near a beautiful part of the park,” she said, referring to the Conservatory Gardens near 105th Street. “Anything with pre-war bones that comes on the market and has a gorgeous view of Central Park will support that price point – even if it is above 96th Street.”

Whether the asking prices at 1200 Fifth Ave., a former rental building once owned by nearby Mount Sinai Hospital, indicate that real estate on Upper Fifth Avenue has entered a new stratosphere is unclear, Ms. Pulitzer said. The development could either prove to be an exception because of its architectural splendor – Emery Roth is behind such celebrated New York gems as the Beresford and the San Remo on Central Park West – or it could be the catalyst that pushes the ultra-luxury market farther up Fifth Avenue.

A Halstead broker, David Owens, said he was confident that both Upper Fifth Avenue and, later, Central Park North would ultimately become megamillion-dollar markets. “It may not ever be as desirable as it is below 96th Street – neighborhoods have certain stereotypes – but the gap is closing,” he said.