How can I make loop cuts the same distance from the edge? I'm trying to make a mesh like this, except where the loop cuts are exactly the same distance x from the edges (this is just a eyeballed approximation of what I'm trying to get):

I've tried looking around for an answer, but the only thing I come across people using beveling or insets, but I need overlapping cuts making the little squares in the corners. I don't want diagonal lines from the corners pointing inwards like this:
The way I would do that is:


Decide the height of the object, but leave the square shape 
Apply two loop cuts
Bevel them 
Grab one side 
Move it on an axis to get the shape you want