Reisner was born and raised in a Jewish family in New York City. After graduating from Cornell University in 1990, he embarked on a 15-year career as a managing director at Salomon Brothers and then Bank of America.
In 1994, while still working at Salomon Brothers, Reisner, his partner Mati Weiderpass and Paul Dominguez founded Watch World International, opening the first Watch World store in New York City's SoHo neighborhood that year. By July 1997, they had opened nine New York locations. The stores featured a range of inexpensive, casual, sport and fashion watches, over 1,000 styles in all. Each of the stores was planned, designed and constructed by Reisner and Weiderpass. By 2000, Watch World had become a national chain of 119 stores. On June 8, 2000, Sunglass Hut International announced that it had purchased Watch World for $30 million in cash, stock and debt.
Reisner is the founder, managing partner and president of Parkview Developers, a developer of residential and hotel properties, primarily in New York City, which he founded with Mati Weiderpass in 2000.
In 2007, Reisner and Weiderpass launched a 109-unit luxury condominium constructed on the site originally built for the New York Central Railroad in the 1930s.
Parkview Developers owns 20 units in the 230 Central Park South building in New York City. Starting in the early 1990s, Reisner and Weiderpass bought roughly half of the apartment units in the 19-story building. They combined, renovated and sold many of the units, including a penthouse sold for $11.9 million in 2014. Reisner lives in one of the penthouses in the building. He has been on the building's board for nearly two decades, pursuing a project to create a "cond-op", a building that is a hybrid of co-op tax benefits and condominium rules. Parkview Developers formerly owned and operated the Carnegie Hotel in Manhattan, near Columbus Circle.
In 2007, after spending a few nights at the Axel Hotel Barcelona, part of a small chain of upscale hotels aimed at a gay clientele, Reisner decided to open a similar type of hotel in New York. He located a vacant space in Manhattan's Hell's Kitchen neighborhood and secured a 49-year lease. The property was originally home to a Travelodge in the 1960s, and was later used as a Red Cross homeless shelter. It had been vacant for several years when Reisner proposed plans to build what would become The Out NYC.
The hotel opened on March 1, 2012. The $30 million entertainment complex consists of a three-story, 70,000 square-foot hotel with 105 rooms, the 11,000 square-foot XL/BPM Nightclub, the Mediterranean-inspired KTCHN Restaurant, an art gallery, outdoor gardens, a spa and a bar. The Out NYC was built after five years of planning. It won a Trendsetter Hotel Award from Fodor's in 2012, and in 2014 Fodor's named its garden one of the world's 10 most beautiful hotel gardens. Past performers at The Out NYC and the XL/BPM Nightclub include Alan Cumming, Cyndi Lauper and Ariana Grande; celebrity guests include Lady Gaga, Perez Hilton, James Franco and Nick Jonas.
In April 2013, Reisner announced plans to open The Out Chicago, a 100-room hotel and resort in Chicago's Lake View neighborhood, modeled after The Out NYC, with a spa, gym, restaurant, lounge and courtyard. In September 2013, the proposal was rejected by the city.
Reisner was sued by architect Paul Dominguez in 2013 for Reisner's failure to properly compensate Dominguez for his work on the Out NYC.
In May 2015, Reisner revealed that he has not been able to turn The Out NYC into a "profitable venture".
On January 22, 2015, Reisner and Sip-N-Twirl nightclub owner P.J. McAteer purchased a strip of commercial real estate along the harbor on Fire Island Pines, a gay destination on Long Island, New York, for $10.1 million at auction. The property includes a hotel, nightclub, restaurant, bar and retail spaces. Reisner stated that he plans on spending $4 million to renovate and rejuvenate the property in 2015 and 2016. The property makes up 80% of the commercial real estate space on Fire Island Pines.
Reisner appeared on season 3 of Million Dollar Listing New York on Bravo. His penthouse duplex at 230 Central Park South has appeared on 30 Rock and in the film Did You Hear About the Morgans? The Out NYC was featured on the sitcom Happily Divorced.
On October 29, 2014, 23-year-old Sean Verdi died of an apparent drug overdose at St. Luke's Hospital in Manhattan after being found unconscious in the bathtub of Reisner's Manhattan apartment.
On April 20, 2015, Reisner and Weiderpass hosted GOP presidential candidate and same-sex marriage opponent Ted Cruz at Reisner's apartment. News of the chat led to controversy in the gay community and calls for boycotts of Reisner's businesses, with the charity Broadway Cares/Equity Fights AIDS canceling a scheduled fundraiser at XL Nightclub in protest. On April 26, Reisner put out a statement on his Facebook page, apologizing for showing "poor judgment" in hosting the event, adding that he made "a terrible mistake." Reisner raised further controversy when, as part of his response to the Ted Cruz scandal, he referred to his gay clientele as "cheap" and "entitled". Contrary to Reisner's previous statements, he did make a $2,700 donation to Ted Cruz — the maximum allowed in a nominating contest — around the time the dinner took place. Reisner also donated to Ron Johnson, the anti-gay senator from Wisconsin, as well as Rudy Giuliani in 2007 when the latter was running for President.
Reisner's brother, equestrian Ross Reisner, was murdered in September 2013 by Brett C. Knight. Knight was sentenced to 22 years in prison for the crime. Reisner is a registered Republican, having donated to both Democrats and Republicans.
Reisner dated Mati Weiderpass for 19 years, before they split in 2012. They remain business partners.