BACK ON THE MARKET -  DEAL FELL THROUGH     This 2-bedroom apartment is in the lively Upper West Side just 2 blocks from Central Park and Riverside Park. The apartment has a bright outlook with tall windows in every room for a light, gracious and airy feel.    Unit 2R, on the second floor, has northeastern exposure, is bright, quiet and faces the back of the building. Enter this apartment through the charming entry foyer. To the left of the foyer is the attractive open plan living area with a great size kitchen and living room that features high ceilings and tall windows for enjoyable light throughout the day.     The primary bedroom is spacious and has open eastern exposure with views to the tree lined backyard. The second bedroom with northern exposure is also of good size and could easily be converted to a home office.    111 West 106th Street is a well-managed and financially sound HDFC co-operative with a total of 15 units. The building amenities include video intercom, laundry room, storage bins and bicycle storage. Washer/dryer and dishwasher installation are permitted in the apartments.     HDFC income caps apply.