With respect to NADA and all of the boxes to add options, I think that is a bunch of BS. When I was shopping there was one particular boat that I looked at and gave an offer with deposit and the broker scoffed at my offer. The broker actually had the audacity to email me an NADA list with every box for options checked in order to get him to his asking price. This included things like K-planes and verious other options that are standard equipment on a 36' performance boat.
I began to discern motivation on the part of sellers and how much they were in the boat for and whether or not they were willing or able to take the hit necessary to see the deal through. Persistance does pay off.
Good luck and I will keep my eyes open!!