As much an icon of London as Big Ben or Buckingham Palace, the curvaceous old Routemaster double-decker is due to be retired next year. But there's no shortage of admirers waiting in the wings to snap up a slice of transport history.
The Routemaster: A 1950s design classic
After many years of faithful service, London's remaining 200 Routemaster buses are approaching the end of the line.
A familiar sight on the capital's streets for more than 50 years, the buses are gradually being replaced by a newer species, more accessible to people with disabilities, parents with buggies and elderly people.
Known to aficionados as "RMs", the huggably curvaceous Routemaster double-deckers, with their trademark bells, half-cabs and open rear platforms allowing passengers to hop on and off, are down to their last seven routes.
All will be gone by the end of next year, although Mayor of London Ken Livingstone has pledged a handful will remain on a number of "heritage" routes.
But the story does not stop here. Given their iconic status, and a disconcertingly devoted fan-base, the market in second-hand RMs is thriving. While some will enjoy an easy retirement in the hands of doting enthusiasts, others look set for lucrative new careers as PR tools.
Revolutionary design: double chassis, light-weight aluminium body, power steering
Largely designed by London Transport's then vehicle engineering manager Colin Curtis
2,876 were built by AEC in Southall and Park Royal, West London from 1954-68
Remaining routes in London: 13, 14, 19, 22, 36, 38, 159
Essex-based bus dealer Ensignbus is witnessing a surge of interest from prospective owners. The company has scores of Routemasters parked up at its site near Purfleet close to the Thames Estuary.
"We get enquiries from all over the world, Australia, Canada, Europe, Asia," says Peter Newman, who owns the dealership. "The Routemaster is iconic, it is London. That's why so many people want one for themselves. We've sold about 150 in the last four months."
His son Steve, who is handling the sell-off believes they are a wise investment. "They hold their value as they're worth a great deal to companies who want one for publicity events," he says.
Dozens of RMs sit in the company sheds awaiting new owners
While some people might baulk at the prospect of handling a 7-ton, 14-foot high, 9.6-litre-engined juggernaut round the local one-way system, you don't actually need a special licence to drive one.
Categorised as "historic buses", anyone over 21 with a normal Category B licence can get behind the wheel as long as there are no more than eight passengers on board. (Perfect for a Cliff Richard-style summer holiday.)
Their resale value is good. Despite age and high mileage, the average Routemaster commands a not-at-all-bad price of £6,000-£10,000 on the second-hand market. Then comes the cost of fuel. Filling the RM's 31-gallon tank will set you back £120. They guzzle fuel at an alarming rate of a gallon every 8-10 miles. The maximum reported speed is 48mph.
To ensure a good number are passed on to preservationists, and remain in the UK, Ensignbus recently invited carefully vetted applicants to a one-off sale of more than 30 RMs at the specially-reduced price of £2,000 each. It's a surreal occasion.
A smattering of buyers bore the traditional bus-spotter trappings of sturdy anorak and notebook. The jewel in the crown was RM541, which first saw duty 44 years ago in December 1960.
Excitement mounts as Steve Newman takes the mic, preparing to allocate buses by drawing numbers out of a hat. And then a series of golden moments unfolds as trusty old buses are united with their delighted new owners. Without hesitation, buyers bound over to their new found pride and joy, jump in the cabs and coax the engines into action.
Soon the yard is full of happily chugging Routemasters, beaming blokes, and diesel fumes.
For Barry Field, this really is a busman's holiday. "I worked on Routemasters for 20 years in the past. I now live in Dorset, I wanted a bit of memorabilia and this offer came along," he enthuses.
"We'll keep it in the garage where I work now and probably take it out for day trips."
Steven Robson from Berwick-upon-Tweed, has more ambitious plans for his purchase. "My dad collects vehicles and thought it would be handy for the business," says Steve, who helps run a honey farm. He wants to use it as a free shuttle bus to the farm.
"There's quite a bit of interest as (Routemasters) are pretty unusual where we are. I've been learning about how to drive it this morning because I've got no idea really. We're going up on the M25, then back up the A1. I've brought a posse here with me in case we get in a spot of bother."
That the RMs have lasted so long is not only testament to the quality of their design but also the high standards of maintenance down the years.
But former Routemaster driver Alan Gregory advises the new owners to lavish their babies with plenty of TLC.
"They're going to a bunch of people who are complete novices. They're going in at the deep end and they're going to have to learn to swim very, very fast.
"They'll need to put some time, effort and energy into them and get them back up to a good condition. They're all working, they're all runners, but now comes the preservation exercise which is big and expensive.
"They're just a giant Meccano set for any kids who ever had one of those."