I would add the following to L124C's comments:
(1) From my research, $20/ft is a good starting point for the basic survey here in South Florida. The mechanic charged me $100 for the engine check and oil samples ($60 for both). The rigger charged me $100 to evaluate the standing and running
rigging. A short haul (4 hours max in the slings) was $200.
(2) I would want to be there when the surveyor does his/her thing. The tough part is staying out of the way of the surveyor. I consider a survey to consist of 3 parts: the hull and structural; the engine and transmission; and the
rigging. To me that would mean an approved or referenced surveyor, a mechanic with factory training on the engine and if possible the transmission, and a well respected rigger.
The surveyor, mechanic, and rigger should provide some kind of report, even if you provide a generic checklist for them to tick off. Most surveyors have their own form but that doesn't mean you can't have your own or list of concerns and ask the surveyor to give extra attention to those areas.
(3) A check of the internet would provide a list of SAMS or IMS members. They have some requirements for certification and may not be as well versed as you'd like. I'd suggest calling a few and asking how often they do sailboats, their credentials, a few references, and get a feel for the competency of the candidate. Some surveyors stick to power vessels. Your insurance or bank may have a surveyor they want to use.