Wow - how lucky are you? Do say more about size, material, condition etc etc.
I really agree with the advice about finding a good surveyor. And asking yourself how to know if they are any good! I don't know where you are and how it works, but in the UK there is a proper association of yacht surveyors and anyone you use should be a member. Also, ask local yacht brokers who they know and rate. Also, you may want some specific expertise, for example if the boat is made of steel or wood or has an unusual rig. Try and find a surveyor with specific knowledge in that area or issue - again by asking them.
It really helps to tell them your position and what you need. You might pay slightly more for the survey but you'll get much better info.
Sorry if this is telling you to suck eggs, but hope it actually helps.