Besides scoring a thousand times with a x-acto, what’s the easiest way to cut open doors, and freight doors? I’m “super detailing” my first structure a DPM Freighthouse. Interior lights, flooring, ivy on the walls, weeds in the gutters, etc, etc.
For the thick DPM & Pikestuff type plastic, I the drill press, band saw, or scroll saw in my wood shop. Then replace the molded in doors, with finer castings, or scratchbuild pieces.
Welcome to the forum. Sometimes a razor saw will cut straight cuts. The knife is sometimes the best and the easiest. Power tools including the dremel tend to leave a lot of flash. I have found that the diamond bits cut cleaner than the steel ones.