"YOU know," the real estate agent sighed as we drove along a muddy road lined with shining new apartment blocks of marble and tinted glass, looking for an address, "if you don't visit a part of Beijing for a few months, you don't recognise it when you go back.
New housing and office developments are transforming the Chinese capital at a dazzling rate. This sprawling oriental city of lanes and low buildings is fast becoming a modern metropolis with tall office blocks and western style suburbs.
Take, for example, the Beijing Riviera on Xiang Jiang Road in the northern outskirts, which advertises itself as an "ideal location for business executives". Its lakeside houses and manicured gardens behind electric sliding gates would not be out of place in a south of England suburb.
Or the Bo Ning Garden apartment complex on Mai Zi Duan Road, promoted in glossy brochures as a "paradise on earth", which has 20 floors of deluxe suites with air conditioning, CNN and a planned golf course.
These new developments contrast with the cramped houses and tiny courtyards of the hutongs, the narrow lanes where most of Beijing's 12 million inhabitants dwell.
I became familiar with Beijing's great urban transformation when hunting for an apartment during a hot, muggy summer. The pollution was at times so bad that the tops of high buildings disappeared in a murky haze.
Until recently, the communist authorities insisted that all diplomats and foreign journalists should reside in four walled compounds, the entrances of which are guarded by members of the People's Armed Police who stand on little platforms under sun umbrellas.
Unofficial contact between Chinese citizens and foreign reporters and diplomats is a risky business for both sides, and no Chinese can enter these walled compounds without official permission. But today the compounds' apartment blocks, some of which are crumbling and cockroach infested, are full.
In recent years many newly arrived journalists have had to live in a hotel for several months until a flat became free. This is usually the Jianguo, modelled on a motel in Palo Alto, California, where journalists meet contacts in cane chairs while a string quartet plays Mozart nearby.
Now foreign correspondents are being officially encouraged to find their own accommodation, as long as it is approved by the Public Security Bureau. This in effect means one of the new apartment blocks where many other foreign passport holders, mainly returned Chinese, already live, along with a few well to do locals.
This is a welcome loosening of restrictions, but it has a drawback. Most "approved" accommodation is enormously expensive. A "paradise on earth" apartment costs £6,000 a month, and life on the Beijing Riviera carries a similar price tag.
Finding a flat elsewhere is not an option. A western journalist who rented a cheap "unapproved" apartment is currently having all sorts of trouble with the police.
We found a (more modestly priced) apartment in a new block which has risen high over the bustling district of Shilipu, which means "five kilometre village".
It has fine views of garment factories and railway lines and of distant mountains, as we discovered one beautiful morning when the summer smog was cleansed from the air by a violent thunderstorm.
All day and night we can hear the distant hammering and banging of construction work, heralding the growth of China as an economic power.
One wonders what Mao Zedong, who died 20 years ago today, and whose portrait still hangs over Tiananmen Square, surrounded now by the shining edifices and neon lights of modern capitalism, would have made of it all.