Most mountains don't have a fixed base camp (as Everest effectively does, simply through the large number of climbers who start from there).
So, for example, one group of climbers ascending K2 might set up their base camp at a certain elevation on one side of the mountain whereas a different group of climbers might set up their own base camp at a different elevation on the other side of the mountain. Other climbers, tackling the same mountain, might not even have a distinct 'base camp' at all, so I can't see how there can ever be any definitive answer to your question.