Resizing CAD files

Is there a better way to prevent sizing of cad files from being off by a small amount over a 75’ distance?

after converting a cad file to dxf then importing into sketchup from same house file the different sections of the house are not exactly the same size. only off by fractions of an inch?

Is there a better way?

What are you converting from?

converting from cad files to dxf to skp. thanks