Adam,
I think the lowest someone could go is to hire an internet junkie/buff/afficiando to design their course.
Most mid range professional gca's take on all kinds of jobs. The year is anchored by a few big jobs - either new or total renovation and much of the time is devoted to smaller fee jobs including consulting, master plans, single/multiple hole designs. There are also the occaisional nine hole, par three and other alternative courses.
Some even take on landscaping, park planning, land planning, etc. Plus, there are always the routings or site feasibility studies for developers that actually get built maybe 10% of the time.
As to the formal interview process, I think the industry average might be one actual job for 7 to 15 proposals submitted and ten might be a good average.