Perfectly situated on the 7th Floor at 730 Park Avenue, this beautiful 4 bedroom apartment affords picturesque exposures to the North and West over East 71st Streetand towards Central Park, as well as absolutely lovely views to the South of the verdant tree-filled Lehman townhouse garden enclave. The sun-flooded rooms of the 10 room residence, with multiple corner exposures, are perfectly suited to grand and gracious entertaining as well as to quiet and cozy family living.     Accessed by a private elevator vestibule, the big rectangular Gallery opens to an elegantly proportioned Living Room with a special peak of Central Park, and to a handsome wood paneled Library, both of which boast wood burning fireplaces. The public rooms also feature a large formal Dining Room facing North over East 71st Street, and a conveniently situated Powder Room.     The private quarters include a very generous corner Master Bedroom with a lovely Sitting Room Alcove, an enlarged Master Bath and a very spacious Walk-in Closet Dressing Room. There are also three additional bedrooms, all with ensuite baths and ample closet space. A sizable Kitchen, Butler's Pantry, Staff Room with Bath and a Laundry Area complete the versatile layout of the delightful residence.     This sought-after prewar full service cooperative is superbly located in one of Manhattan's most desirable residential areas on the west side of Park Avenue at the corner of 71st Street. The distinguished and impeccably staffed building provides its tenant shareholders with a private gym and storage areas as well as a meticulous in residence superintendant.