I currently live in a 550 sq ft 1-br apartment, and it's actually quite comfortable. Adequately sized kitchen wirh a kitchen island (since I like to cook), bedroom big enough for a queen bed, a not-cramped bathroom, and a living room. Plus pretty decent closet space and in-unit laundry. Tbh, my only wish is that the living room were a bit bigger so I could have a proper sofa and a proper desk for days I work from home. Currently just rocking a desk and an armchair and a TV stand. For a family, I'd definitely want closer to 1000 sq ft.