In the attached I used LODs to create a uniform reference line across all three sheets. Since the LOD is a FIXED LOD, I put the Segment filter "in context" so that it governs the LOD. (Usually FIXED LODs get evaluated before filters, unless the filters are in context.)
I'm grabbing the largest bar, and making a reference line 110% of that largest value. (If you need to do a minimum one, you can model the same principle for that.)
For now the reference line is displayed, with a label, but you can set the line to NONE and the label to NONE, and it's invisible to the user.
The axes are all set to automatic now. Let the reference line govern the extents of the axes.
Looks like this approach is going to work.