Britain's Most Expensive Houses

This programme features a grade I listed terraced home for sale overlooking Regents Park Lake. Built in 1822 and designed by renowned Regency architect John Nash, it's worth an eye-watering £29million, making it one of the most expensive homes in the UK. Also in London, managing director of UK Sotheby's International Realty Guy is invited to sell a rather unusual houseboat boasting five bedrooms and three bathrooms.

Broker Constance is on a mission to get the listing for Laura Comfort's £12.5million home as the celebrity singer wants to downsize to a £4million pad in Chelsea. Managing director Guy values a quaint Tudor cottage in Henley on Thames - a little corner of paradise that owner Brian is selling for the not insignificant sum of £1.75million. It boasts a swimming pool and a shower in a former phone box.

Sotheby's managing director Guy hopes to secure the listing of a £6.5million 14-bedroom, five-acre Grade II listed manor house mega home onto his books. Aston Tirrold in Oxfordshire boasts six reception rooms, a tennis court and a huge outdoor pool, and has been home to the same family since 1975. Broker Kenrick heads to Camden, north London, to try to secure the listing of an uber-modern glass building apartment with three bedrooms, three bathrooms and a 900-square-ft roof terrace.

Sales broker John has a vast family home to sell in the stunning New Forest. Surrounded by a national park and with 26 acres of grounds, including a swimming pool, an orchard and private woodland, this 12-bedroom home built in 1897 has an asking price of £9million. Meanwhile, managing director Guy and Aoife work on one of their smallest properties - an industrial-style one-bedroom pied-à-terre in Pimlico in central London, which belongs to the chief executive of Brighton Football Club.

Sales broker Diana tries to convince property developer Kam that she's the right person to sell his £30million mega-home in Mayfair which boasts a swimming pool, a gym, a steam room and a glass lift. Christine enlists the help of fellow sales brokers Tessa and Amy to help close a deal on a Grade I listed Georgian townhouse in Bath and a modern country home just outside Henley. In London, Aoife has secured the listing for a new development of 15 apartments in Bayswater with a combined potential sales value of £65million and Natalie thinks she might have found the first sale.

Amy, director of the country office, visits a 1930s property in Surrey boasting eight acres of award-winning grounds, an on-site recording studio, circular rooms, horizontal curved windows and terraces with views of the gardens. Once belonging to Roxy Music guitarist Paul Manzanera, it's an exciting listing for Amy who is on the hunt for a buyer willing to pay £5.45million or a tenant with £20,500 per month to spend. Mo entrusts Natalie with a new listing - an enormous three-storey converted factory in the heart of Spitalfields worth £2.3million. Managing director Guy has a listing for a five-bedroom apartment in Cadogan Square, Knightsbridge with interiors by award-winning Croatian designer Victor Udzenija. He reaches out to superyacht broker Andrew for help finding a buyer for the £25million property.

Director of the country office, Amy has a listing for a £7.25million house in Oxshott, Surrey. Just an hour outside of London and close to the Chelsea Football Club's training ground, she is looking for a wealthy football fan to buy the property that boasts a large garden with an outdoor jacuzzi, sauna and entertainment area. Managing director Guy visits an 18th-century chateau in the Loire Valley with its own 18-hole golf course that is available to rent for £30,000 a night. In London, Diana meets a millionaire whose private jet business is booming and is looking for a pied-a-terre to buy or rent. Developer Kam, who is restoring the former stately home Doughty House in Richmond Hill expects that, once completed, the super-mansion with 12 bedrooms, a ballroom, a pool, a spa and a bowling alley will hit the market for £100million.

Guy and John visit Cheshire's Golden Triangle to conduct a valuation on a country retreat featuring an indoor spa and panoramic views. Jaishree puts a two-bed apartment in Chelsea on the market for £2.6million with a friend in mind as a potential buyer. Director of the country office, Amy, attempts to close the sale of a Grade II listen 17th-century watermill in Solihull that has been sympathetically restored by its owner and has been on the market with other agents for four years. In Hampstead, Lee gets involved with a unique development that he hopes to sell for over £10million and John in Brighton is selling a Regency townhouse worth £2.25million.