The first thing you notice at the entrance of Dennis Lynch’s houseboat is a spiral staircase a few feet from the door. Once you get past it, though, Mr. Lynch’s vision for his floating home becomes clear.

Stained glass hangs on almost every window, wall, and door. To the right is a 12-foot round window – the top half, which Mr. Lynch made, is cobalt blue, and the bottom is an upside-down antique arch. A fairy illustrated in different shades of blue hangs in a smaller window. Even the kitchen cabinets made way for stained glass. Works of green and purple grapevines set against a blue sky are mounted in the doors and illuminated by lights from inside the cupboards.

Mr. Lynch, who makes original glass artwork and restores antique pieces, has collected boats and stained glass for 40 years. This houseboat is the culmination of his efforts. Until recently, it had about 100 pieces of glass on it – so many that when Mr. Lynch moved half of them to an upstate cabin, the boat floated two inches higher. And those pieces comprise just a fraction of his 1,000-piece collection. According to a glass artist and restoration expert, Michael Levine, Mr. Lynch has one of the largest collections in the country.

The boat is also filled with other oddities Mr. Lynch has collected on his never-ending search for glass. In the living room, a 60-year-old cactus sits on top of an African drum with a zebra-skin top. A nearby table is covered with Buddha statues. But glass dominates the house. Up the spiral staircase is a third floor surrounded by 22 sliding-glass doors that support another slew of stained-glass pieces leaning against them.

Mr. Lynch – who answers his phone saying “Cap’n Dennis” – splits his time among the boat, the cabin upstate, and an Upper West Side apartment with his business partner and significant other, Felice Perlman, a psychiatrist. They came to own a houseboat in 1998 after a friend with a grudge told them about a fabulous houseboat costing nearly nothing. After a wild goose chase around the city, they realized the boat was a phantom, but the idea stuck.

They found their houseboat the following year in Seaford, on Long Island. Transporting it presented a problem, though, since the houseboat doesn’t have an engine. Towing it requires flat seas, so at 2 a.m. on a November morning, Mr. Lynch and Ms. Perlman snuggled in sleeping bags while a tugboat pulled them toward their new home. The boat is now docked at Metro Marine, a marina on Westchester Creek in the Bronx.

Mr. Lynch, who is 64, grew up in a tiny town in Oregon, the son of a carpenter and the youngest of five brothers. His mother enrolled him in ballet class so he would have something to set him apart from his siblings. Ms. Perlman says, “I don’t know whether it was the pleasure of being around half-clad 14-year-old girls or what,” but the dancing stuck. After high school, Mr. Lynch spent two years in the Army and a year and a half as a carpenter in Alaska before moving to New York to dance professionally. His best friend owned an antique store in the city. “I fell in love with antiques, but I really fell in love with stained glass,” he says, citing “the feeling it gives when the sun’s on it.” In a certain piece of St. George slaying the dragon, he says, “Only at sunset did the flames come out of the dragon’s mouth. Things like that happen with glass, not with other kinds of art.” It was an affordable hobby at the time. “No one liked it,” he says. In the early ’90s, he met Ms. Perlman, who was already a flea-market enthusiast, and she began focusing on glass as well.

Around the same time he discovered glass, he bought his first boat. “I bought it for $1 a foot under water,” Mr. Lynch says – in other words, the boat was sunk. He fixed it up and sold it two years later for $1,000 a foot, with a dozen pieces of stained glass included. Since then, he has bought and sold another 40 boats.

“I’ve always loved boats,” Mr. Lynch says while showing off his boat. “And it’s mine. I can do anything to it I want. It’s not like an apartment, where you can’t put decorations on the outside of the building, you can’t add another room to it. There’s a lot of ‘can’ts.'” The summer after they bought the houseboat, Mr. Lynch, Ms. Perlman, and several friends built an extra floor – hence the spiral staircase – and decorated the outside to resemble a 16thcentury Italian gondola. Out of 22 statues originally mounted on the boat, five remain, including two 12-foot dolphins frolicking around that huge round window and a statue of Venus gazing across the creek at the Hutchinson Parkway.

Living in and maintaining a houseboat requires a certain perseverance. And it’s getting more difficult to find a place to keep a houseboat. Many marinas don’t allow year-round docking. The 79th Street Boat Basin, run by the city Parks Department, is a notable exception, with about 35 boats docked year-round, but it hasn’t issued any new year-round docking permits in more than a decade.

Once they get past the obstacles, though, houseboat denizens cherish the freedom, quiet, and price of living on a boat. “It’s certainly an economical way to live,” Ms. Perlman says. Owners don’t have to pay property taxes, though they do have to pay about $400 a month in rent to dock at the marina. Houseboats often cost less than $50,000, which leaves room in the budget for amenities. Two other houseboat owners, Dale Eggers and Neil Corwin, who live next door to Mr. Lynch, recently installed a hot tub on their roof. “No taxes. I like that. No mortgage. You’re free to be,” Ms. Eggers says. With only four houseboats parked at their quiet marina, they just may live in the most secluded neighborhood in New York City.

While his other boats provided Mr. Lynch with amusement and income, this one has given him a home. Modern technology takes care of certain occasional disadvantages. Flushing the toilet requires an extra step – briefly turning on a pump, which transfers the sewage to a tank at the marina – but otherwise, the bathroom looks like one you might find in any landlocked home. Mr. Lynch sleeps on a mahogany canopied bed on the glass-encased top floor. Insulated windows keep the boat about 10 degrees warmer than outside, staving off the winter wind. After 40 years of restoring boats, Mr. Lynch may finally have found what he’s been looking for. “This is the last one,” he says. But then he adds, “I always say this is the last one.”