Sometimes it is better to build a layout in modules, or work on just half of the layout to start with. A half-sized layout is not only quicker to build, it will provide you with a good guide to the costs and time involved.
It's a good idea is to paint the top of the baseboard gray when constructing your layout. Patches of track work where the ballast has not been secured properly will not stand out as easily. I know it is a simple idea, but it is amazing how many people don’t do it.