I'm seeing a lot of houses with diagonal rooms (instead of square or rectangle) is that normal? 

I drew the red rectangle island in the mid of the kitchen and asked if my contractor can run the pipes from the kitchen & bath (in the right) from the floor (I am pretty sure the joists run this way).

The compressor units for mini splits are awesome- quiet, power savvy, and small, you can tuck them in and hide the easily.  3) I'm not HVAC experienced, other than casual interest, but I've seen on This Old House the installation of smaller 4" ducts that run to a smaller room "port" that is circular, instead of a big vented rectangle.  

In other words, all squares are rectangles, but not all rectangles are squares. 

It is a approximately 28x11.5 foot rectangle with a 9x5Foot master bath.

Some folks cut the stands in half which mounts the sign lower to the ground, but is more wind-resistant.I'm asking about the vertical rectangle signs with the steel "T-bar" like the home builders use.

My roof area is very simple, like a rectangle, not walls, no curbs, no valleys, just a simple flat roof about 2200 SF. 

It is essentially a rectangle with all the plumbing stuck together to make construction simple.  

The blue rectangle is the property in question and the gray is the street.

Kind of like all squares are rectangles, but that doesn't mean all rectangles are squares.