Assuming you work, say, 3 days a week (and ignoring summer for now), I would go for something like:
work:
4-5 skirts/trousers/dresses
8-10 tops/shirts
2 cardigans/blazers, more if your tops aren't warm enough
2-3 pairs work shoes/boots
accessories
SAHM-ing:
5-6 bottoms/casual dresses
10-12 tops (I have fewer than this, and it's always a bit of a race to make sure I have enough clean)
3-4 jumpers/cardigans
accessories
3 pairs boots/sneakers/whatever you wear on your feet normally
misc
1 'sensible' warm waterproof coat, if you feel you need such a thing (I don't - I hate hoods so always use an umbrella, so get away with just one overcoat)
1 nice warm wool coat that will do for work as well
1 lighter coat
1 dress that will dress up or down for smarter evening things, weddings etc
But the specifics really do depend on your personal style. I tend to wear a broadly similar 'look' most days, so it is easy to mix and match my tops and bottoms together, but if you like to really mix it up, that is less easy, so inevitably you need more clothes.