HOUSE OVERSIGHT 022437 the neighborhood, will have 6,000 square feet of amenity space that ranges from music rehearsal and art rooms to a gym and children's play area. Apartments go on sale this fall, with pricing in the $1.3 million to over-$12 million ballpark. The latest rendering for skyscraping Citizen360. Photo: SHoP Architects "The site was highly undervalued because it was so far east, and there were no good transportation links, and people just weren't interested or willing to go there. But we saw opportunity," says Barbara van Beuren, Anbau's managing director. "I think the absolute prices are manageable. This is not a building full of $10 million apartments." Still, it points to a future far more expensive than the current data shows. Just one block from 113-year-old Jewish bakery Glaser's, which churns out delicious black-and-white cookies, Citizen360's shimmery facade will rise 410 feet above street level. But trumping them all will be DDG's under-construction goliath on 180 E. 88th St. At 521 feet, it will be the tallest structure on the Upper East Side north of 72nd Street. Its 48 apartments with 16- foot ceilings and custom lobby artwork launch sales this fall, with two-beds starting from $3.4 million, three- beds from $4.5 million and four-beds from $7 million. It's not all about living among the clouds, though. Michael D'Alessio, president of Michael Paul Enterprises, oversaw the overhaul of two smallish rental buildings east of Third Avenue into boutique luxury projects. "They were prime locations for condominiums catering to families," says D'Alessio of the projects, 225 E. 81st St. (a.k.a The Justin) and 554 E. 82nd St., which have nine apartments between them. "They are three or four bedroom units, with big living and dining areas with fireplaces, and they all have outdoor space." Six have been snatched up, with asks ranging from $2.25 million for a two-bedroom to $5.99 million for a four-bedroom. A fireplace-spo