Well, remember that OKW has no elevators, except in bldgs 62, 63 and 64. SO with strollers, you may want to request ground floor...but that also increases the probability to get a HA unit. So if you are in a studio and need a bathtub, request that, too, as HA studios have roll in showers and no tub.
On the other hand, if you are in a studio and have a lightweight stroller you don't mind taking up stairs, request a 2nd floor room, as none of them, except in bldgs 62, 63 or 64, are HA, so the 2nd and 3rd floor studios will have bathtubs.
This won't be problem if you have a 1 bedroom unit, as all one bedrooms, even HA, have a tub and a free standing shower.