1200 sqf is on the larger side of a 2br apartment but rooms are not normally 300 sqf. A 2/2 apartment usually has following "rooms": 2 bedrooms, 2 bathrooms, 2 storage closets, HVAC closet, laundry, and a living room combined with kitchen. Out of these, the living room/kitchen area might be 300 sqf or more, the rest of the rooms are much smaller. The OP likely meant 25% of living space, e.g. taking away one bedroom and its bathroom and storage since your working there would render them unusable to other people living in the same household.