you could just use the cut faces tool. that will create an edge in a straight line. then delete everything on one side of the cut.

Have you tried sketchUp? (i'm sure you probably have) it just might be quicker and more accurate to model something in that and export as an fbx or obj (pro version required). you can then just render in maya. Vray is available for sketchup tho.
i hear the 3D in autoCAD is better now too.

also from what i can tell, most visualisers use max over maya.