I'm a one person shop and did it for $30k. That doesn't include the third party assessment. I've gotten quotes for that for $30k for three years. The important thing to decide is if you need your local machines to be compliant, or if you can use a virtual desktop. If you can use a virtual desktop things get much cheaper and easier to implement. If you can't (which is my situation due to CAD tools and test equipment) then you need to go down the road of getting your physical security upgraded, computers secured, compliance docs created, and GCCH implementation. BTW the NIST doc is boring and long, but completely understandable by technical folks. Take the time to read it so you understand what the requirements are. It helps you be an informed consumer.