Lady Gaga is looking to buy a penthouse apartment near her childhood home on Manhattan’s Upper West Side, Page Six can reveal. The singer has been searching for properties in the $15- to $20-million range, with outdoor space or a terrace, near her parents Cynthia and Joe’s place on West 70th Street for herself and her fiancé, actor Taylor Kinney. Gaga, 29, has been renting a $22,000-a-month duplex at 40 Central Park South for a number of years, but now wants to buy her own place in the city. A s