Panorama goes undercover at one of the UK’s biggest estate agencies to investigate claims it’s not acting in the best interests of customers. Reporter Lucy Vallance uncovers evidence the company favours buyers taking out mortgages brokered by the company itself, over the interests of other potential buyers. She also speaks to a whistleblower who worked at another big estate agency, where staff were under pressure to sell add-on services and were incentivised by a commission scheme to get sellers to drop their house prices. Both companies say they treat customers fairly.