Room in sqm isn't too important if the cat gets enough stimulation to not be bored. You can easily use the walls and ceiling to create an adventure playground for young cats. >non-human company is why I want a cat after all.
It's not a chill 10+ year old cats company though, in the worst case scenario you'll have to take care of a manipulative toddler on speed foor about the first year and you should be prepared to be very annoyed:
- demans playing chase and fight for 20 minutes every other hour and also at 2 and 4 in the night
- learns quickly that even a tired you will get up to 'play' again if it sreams really loudly, destroys your favourite furniture or playfully attacks harder and more often that usual
- no way to get a nights sleep than to leave it locked in the bathroom howling