What I do is add a scale factor to all of my graphics commands so they can be redrawn larger or smaller as needed.
A random line of code from my cabinet design program.
ds=drawing scale
Code:
#cp.1, "line "; xd; " ";590-(offfloor*ds)-(ch*ds)+(tr*ds); " ";xd; " "; 590-(offfloor*ds)-(br*ds)-(uclo*ds)-(mr*ds)