We are doing three inspections - a foundation (which should already be done), a framing, and a final. It will cost us $350 for our 1800 sq ft + basement house in the midwest, but I imagine prices vary greatly. When we get our report for the foundation walk through, I'll share it here.
Our main issue is that we're not in construction, and while we can go to the site, we really don't know what we're looking at besides floorplan issues. An independent home inspector (this is separate than any sort of certificate of occupancy or code inspection) can find issues or flaws that may be covered up during the final inspection, or just give you peace of mind that your house is built to code in case your city inspections are not that rigorous.
That's not to say that they're foolproof - since I don't know much about the building process, I won't be able to catch something our inspector misses, but he came highly recommended.