For one thing, the rearrange-it-later approach may simply mean that once you’re set up, the haphazard plan becomes the permanent plan, thanks to sheer inertia (it is a pain to move furniture, after all, especially when some of it is as heavy and awkward as workbenches and stationary tools). For another, too little advance planning may mean you buy a power tool that’s too big for your space.
One of the challenges we all face is how to move machines into a home without damaging the home, the machinery, or yourself. I actually had to bring things through the front door, and across hardwood floors, and turn 90° to descend the stairs into the shop. To protect the floors, I laid down sheets of 1/2" MDF that I could use later. On the wooden stairs, I used three strips of softwood strapping, held with wood screws to the stairs. I mounted a 2x4 baton to the wall studs at the top of the stairs, with a 5/16-inch eye-bolt through it.
After a permit has been issued, the building inspector will want to be notified at various points during your build in order to do a site visit, walk around and inspect the details to make sure that they meet code requirements. These inspections are commonly at the point where excavation work is complete, when the foundation is completed but before back-filling, when framing and all structural work has been done, after the installation of the insulation and vapour barrier, and then a final inspection after everything is complete. You may need to have a separate plumbing inspector if you’re adding or changing plumbing fixtures, and electrical work will need to be inspected by the appropriate electrical inspector (in Ontario, the Electrical Safety Authority). In my experience, inspectors appreciate good work, a clean, safe site, and are willing to work with homeowners and builders to make sure that the work will meet code and will endure.
Let’s be clear about one thing: No workshop is perfect for everyone. If there were, I could simply give you a precise plan to follow with clear dimensions. Every person who comes to the hobby, avocation, or profession of woodworking has his own particular collection of tools and his own peculiar work style, skills, and desires for the kind of woodworking he wants to do that gives him a unique approach as to how he will lay out a shop: where the tools should go, where lumber and supplies are stored, and how much bench area he needs.