Estate agents: "They tell lies. They cheat people."

'You'd get a better response if you said you're a mass murderer," says one of the estate agents in Under Offer: Estate Agents on the Job , a new six-part BBC Two series which looks at the very different working days of 11 agents from around Britain.

Estate agents, it seems from the entertaining observational documentary series which began last night, know they’re not the most liked profession in the world. And whether it’s cool-eyed pragmatism or skin like rhino hide, or a mixture of both, none seemed to mind or be particularly hurt by the general perception, all being too busy selling to care.

Straight-talking Lynn Blaney of Robinson's Estates, who heads up a small agency in a depressed corner of Durham, knows the image well: "They tell lies, they cheat people, that's people's image of estate agents," she said, although every minute that we saw of her working day told a different story. Her area, Spennymoor, a former mining town in the North East, has some of the cheapest properties in Britain and a third of all her sales are repossessions. The cheapest repossession house she sold went to auction for a pound and last night's Under Offer followed her campaign to sell one of the most expensive houses ever to come on her books: a large refurbished detached house with an asking price of £249,000, and an owner with a dedication to bling furniture and leopard print. At five times the average price for the area, it had been on the market for four years and despite several price drops still hadn't budged.

“The majority of people still have unrealistic expectations,” said Blaney – agents are nothing if not diplomatic about their clients – before attempting and failing to encourage her client into another price drop. When new photos and a new weblisting of the property still hadn’t attracted even a single call, Blaney and her colleagues brainstormed.

"Laminated posters," said one; "Why don't we try the car?" offered another, "that'll get attention." and so we saw Blaney driving around in the company's car – an attention- grabbing Robin Reliant, like the three-wheeler Del Boy had in Only Fools and Horses , on which the very optimistic agent had stuck small laminated posters of the house. No luck with that either.

At the other end of the housing market – it could have been another planet so different were the experiences – is London and the hugely moneyed world in which Gary Hersham of Mayfair estate agents Beauchamps operates. He travels to viewings in a chauffeur-driven car (saves time on parking) and sells houses with price tags that are frequently well north of £10 million. These days his clients are often Saudi or Russian and typically in their 20s or early 30s.

He took the cameras on a tour of a new listing – a 1300.6sq m (14,000sq ft) house in Mayfair for £39 million – fully furnished right down to the crockery in the kitchen because the super-rich prefer it that way. The buyers he meets, he said, are so rich, billionaires several times over, that multimillion pound prices don’t really faze them. “Small change,” he said. The upper rich, he said, look for immediate gratification. “At that level the super-rich don’t have time or patience, they want to move into a house fully furnished.”

We saw him showing a prospective buyer around a six-storey “doer-upper” in Eaton Place, one of the most desirable addresses in London, and with a price tag of £27 million. The buyer was a developer, who coolly appraised the space, taking in all Hersham’s patter about mews potential and the rest, but without saying much.

When it came to talking money, though, as the Under Offer narrator, the superb Derek Jacobi, said, "Gary and the developer are about £10 million adrift." The estate agent was philosophical. "He needs to make a 20-25 per cent developer's profit and the figures just didn't stack up for him." They would, however, Hersham felt confident, stack up for someone else. And when they did he was set to make a cool £500,000 commission.

Under Offer: Estate Agents on the Job continues on BBC Two on Wednesdays, 8pm