Madonna has reportedly splashed out £6 million on the house next door to her London home.
The superstar, who is said to already own five properties in the British capital, snapped up the 10-bedroom Georgian townhouse in Marylebone last week.
It is now believed Madonna - who lives in the eight-bedroom house next door with husband Guy Ritchie and children Lourdes, 10, six-year-old Rocco and adopted baby David - could link the two properties to make one huge home.
The 48-year-old star purchased the house from designer-developer Paul Davies, who paid just £3.1 million for it last year.
A source said: "Madonna has been a very shrewd property investor - this is her fourth in the area. She knows the prices are much lower than in nearby Mayfair but that the area is hot now. She has said she'd like to buy the whole street.
"She was really keen to get her hands on this house because she knows once Paul Davies starts developing properties an area can skyrocket. He rejected all her offers for eight months, but finally agreed to sell."
As well as their five London properties, Madonna and Guy also own the 1,200-acre Ashcombe Estate in Wiltshire, a New York apartment and a £8 million Beverly Hills mansion.
Despite buying another home in London, American Madonna has complained about British workmen.
She said: "I can't believe how people don't like to work. The week starts at noon on Monday and ends at noon on Friday. I'M used to people in America working seven days a week."