Find a pair of connecting cabins. As you look at them from the hall the one on the right has the bed by balcony. The one on the left has the bed by the bath. All balcony cabins follow the balcony, bath, balcony, bath balcony pattern so just work your way down the hall.
Or, find a room that holds more than 2 guests and it will always have the bed by the bath and the cabins on either side of it will have the bed by the balcony.