His interest may sound weird, but he's not alone. There are about 15 private bus owners in Hong Kong, according to 22-year-old salesman Eddie Wong King-him, who owns an ex-China Motor Bus.

Local bus collecting started in the early 1990s when bus companies began retiring non-air conditioned models. The process accelerated in 1998 when New World First Bus took over Hong Kong Island routes from China Motor Bus, launching a mass replacement programme. Other companies followed suit.

According to local bus companies, some retired Kowloon Motor Bus (KMB) vehicles are sold to England as school buses, and some former China Motor Bus (CMB) vehicles go to Australia as open-top tourist buses, but most wind up in scrap yards.

But some of these 'old soldiers' have escaped the wreckers' yards thanks to bus lovers. According to Lee Tin-yau, honorary secretary of the Hong Kong Transport Society fan club, there are up to 20 buses being preserved by individuals, both single and double-deckers.

Bus collecting isn't new. Enthusiasts in Britain and Australia have been buying them for years. They have owners' clubs, rallies and bus museums.

The first known collector in Hong Kong was a trader in the early 1990s who used to buy and sell old public transport buses to the mainland. He kept rare models for himself. About the same time, another man bought some CMB 1960s vehicles, and members of the Hong Kong Transport Society bought four non-air conditioned buses.

Bus owners come from all walks of life. The youngest is a 16-year-old student and the oldest a wedding photographer in his 30s. There's also a salesman, a Cathay Pacific employee, a printing shop assistant, a bus company worker and a bus engineer.

Ng, an electrician, is the latest recruit, his move born out of a life-long passion for buses. 'I don't know why I like buses so much,' he says. 'It may be inborn. I was happy whenever my mother took me to ride on buses when I was small.'

Over the years, Ng has collected more than 100 miniature model buses, never dreaming he'd one day own the real thing. In January last year, Ng went with a friend, Tong Chung, to a Yuen Long scrap yard and was shocked to discover 10 old buses being dismantled.

'I felt very sad,' he says. 'The buses served us for so many years, and this was their fate. Many of them could still work.'

So, he decided to save one: a KMB Mercedez Benz 0305, which had served on Tuen Mun Highway Route 68 or 68M between Tsuen Wan and Yuen Long, and on which he used to ride.

The 20-year-old bus, originally worth $1.4 million, cost him $30,000. With the help of a Citybus driver, he moved it to an open field in the New Territories. Two months later, the bus was seriously vandalised. 'It was damaged so much that I had to take it to the scrap yard, where it was dismantled,' Ng says. 'I felt heartbroken.'

In the yard, he spotted two buses of the same model. One was being scrapped, and the other was awaiting demolition. He bought the latter by trading his wrecked bus and paying an extra $5,000.

Ng says the bus seems to have a mind of its own. He remembers that when they drove it away, it stopped in the middle of the road. Ng told Tong that if the bus didn't work, he'd take it back. 'Magically, after I said this, the bus started and we moved off immediately,' he says.

And so his new life as a bus owner began. 'I sometimes sit on the bus by myself and reminisce about the past. It's relaxing,' he says.

Although Ng's tailor father has been kept in the dark about his hobby, his mother knows his secret. 'When I told her I had bought a bus, she was shocked and said, 'You're crazy, you've wasted so much money'.' Ken Lau Wai-yi, one of Ng's school friends, says: 'Tony is crazy. We were really shocked that he bought a bus.'

Parked in the centre of a public parking area, his bus attracts a lot of attention. Its faded yellow paint tells the story of its long journey. And the sight of Ng and his friends happily cleaning it shows how much the bus is treasured. But keeping a bus isn't cheap or easy. Finding and paying for storage and security are problems, while maintenance is expensive and spare parts hard to find.

Ng says he can afford the monthly $1,000 parking fees, but he struggles to maintain the bus. It hasn't been running since the end of last year.

'I don't know how to repair it,' he says. Ng has asked the bus companies for help, but KMB says it doesn't provide such services. The New World First Bus company says it's considering his request.

Facing the same plight is Eddie Wong and his friends. A bus technician mate occasionally comes to help them repair their buses, but it takes a long time. 'I've thought about giving it up, but other owners said that I've spent so much money and effort on it that I shouldn't.'

Some of the collectors store their buses in two high-fenced repair yards in the New Territories for security reasons. Among the nine buses there are a Leyland Olympian, a Mercedes and a 20-year-old Dennis Condor, which is owned by Wong and his friends.

Co-owner Gary Cheng Kai-cheung, 20, says the buses have cemented their friendship. They celebrate birthdays in the bus, and they've slept and played cards in it during holidays.

Boarding the bus carrying the route plate 'North Point 112' on the front, Wong sits in the driver's seat, hands on the steering wheel, staring out the windscreen. Spare parts and tools litter the floor. The vehicle is obviously a work in progress. Wong and his friends bought the bus in 2001. It's only been driven twice on the open road.

'Hong Kong's roads are so congested, we're afraid of causing an accident if we drive in the city,' Wong says.

Another bus owner, who would give his name only as Mr Wat, says people have mistaken his KMB bus for the real thing. 'We were testing the bus near the parking area when some people tried to stop us and get on. We just ignored them and went on,' he says. Once or twice a month, he comes with other owners to clean their vehicles and take photos of them. The fans plan to organise a bus exhibition to show off their collections.

Hong Kong buses are also popular with overseas collectors. The Hong Kong Transport Society's Lee says that at least five double-deckers from Hong Kong are preserved by British enthusiasts.

Last year, Australian bus driver Andrew Haviland, who has a fleet of 15 buses, came to Hong Kong and bought two KMB double-deckers from a scrap yard near Yuen Long. 'I fell in love with Hong Kong and its buses,' says Haviland, 29.

He plans to ship the buses to Australia in a few months. 'I'll keep them in a bus museum and run them occasionally through the streets of Sydney,' he says.

Meanwhile, Ng says that, despite the difficulties in maintaining his bus, he won't give up his hobby.

'Some people say I'm crazy to keep this bus, but I don't think so,' he says. 'We just have different values. The experience of keeping a bus has taught me that nothing is impossible.'