What Martin says. Besides, if you look hard enough you can buy kits on the used market, often in pristine condition. I bet I have assembled 25 such kits, but I have the skills to fix damaged pieces and fabricate new parts.
Or, you can buy poorly assembled kits for cheap, take them apart, and assemble them into a work of art. Varney's B&O Ten Wheeler is in that category - look for around $150 or so.