1953 house with septic. Cast iron waste pipe from crawl space to septic, about 30 feet. I gather that the cost of having a plumber dig up, remove, and rerun whole new waste pipe is expensive. I assume that the expense is in the labor and that the actual plumbing is pretty straight forward. Is this true? Could someone do it themselves if they are willing to put in the elbow grease or is there more to it?