Too many, 18 when I bought the house, 8 beds, living, family, den, two kitchens, two laundry rooms, three baths, tore down illegally built part of house that had 4 beds and a bath to build a garage, now only 13 rooms.
Moving next month to 9 rooms, 3 beds, 3 baths, open living/kitchen/dining, family room, laundry. Should be easier to clean.
9.
Utility room, sauna, living room, 2 toilets, bathroom, kitchen/dining room, 4 bedrooms, upstairs living room, dad's "radio" room and dad's "laboratory". That's 14 rooms. We're a family of six so the large amount of rooms is no surprise. This whole house was built from scratch by my dad and my mom's dad.
We also have a balcony, a cellar by the back of the yard and 2 garages. An open garage for my mom's car, and a locked one for my dad's tools (his van is too high to fit inside, so he parks it in front of the garage door).
I park my car between the locked garage and the backyard fence, and my sister parks her moped where ever it happens to fit.
My old one had 5 (2 bedrooms, bathroom, living room, kitchen) or 6 counting utility room. Now I have 8 (3 bed, 2 bath, kitchen, living room, study, dining room).
Don't count cupboards/box rooms/garages/attics/basements unless actually lived in.
Just curious.