There are three houses with one staircase, and the middle house of each unit is protruding. I want to buy a house with two ends, and the north and south are transparent, but I don't know which unit to

There are three houses with one staircase, and the middle house of each unit is protruding. I want to buy a house with two ends, and the north and south are transparent, but I don't know which unit to choose. When buying a house and choosing a floor, we will generally consider these aspects: 1. The total number of floors of high-rise residential buildings. 2. Environmental requirements for high-rise residential buildings. 3. The convenience of life. 4. No matter which floor you choose, lighting is in the first place. 5. Family size and health status. 6. If you believe in geomantic omen, the zodiac and floor geomantic omen are also aspects to be considered. Simply put, the higher the floor, the less shelter, and the better lighting, which is more suitable for young and middle-aged people to choose and live. For the lower floors, it can avoid noise and dust pollution, and these floors are more suitable for the elderly to live in.