A small house in the country? a house with no stairs? a house which is part of a bigger building ( american english)?

1. А small house in the country? Сottage.2. А house with no stairs? Вungalow.3. А house which is part of a bigger building ( american english)? Apartment.4. А house which is part of a bigger building( British english)? Flat.5. A house which is not joined to another house? Semi- detached.