I have 3:
1) 18.2 cf fridge ferment chamber, that also serves to cold crash prior to racking to kegs.
2) 7.2 cf 3-faucet chest freezer kegerator holds four ball locks + 2 more on compressor hump for conditioning/carbonating
3) side by side fridge/freezer, with half of freezer for hops, and fridge can hold two ball locks + 2.5 lb co2 cannister plus bottles.
The side by side plus my food fridge (not previously listed) make ice, which helps having two ice makers for filling coolers, house parties, etc.