Cats are suitable for upstairs living. Cats are pets that thrive in indoor environments; they are generally quiet and don't make much noise. Compared to dogs, cats are smaller and don't require much space to move around. If you plan to keep a cat upstairs, please keep the following points in mind:

1. Provide adequate space: Although cats have a relatively small range of movement, they still need some space to stretch their bodies and play. When keeping a cat upstairs, you can provide them with a cat tree or some toys to ensure they have enough space to move around.
2. Safety Measures: Ensure the upstairs environment is safe for cats. Check the safety of windows and balconies to prevent cats from jumping out or getting injured accidentally. Also, ensure there are no hazardous items or chemicals upstairs to prevent cats from coming into contact with them.