If it's anything more than an open daysailer where everything inside is visable to the naked eye, you need experience to judge for yourself, or a surveyor
who is familiar with the make and model of the boat.
If the surveyor
is not familiar with the make and model of that boat, he may be unable to do the kind of job you really need.
Someone remarked that many folks are surprised to find that boat repairs
cost five times as much and take ten times as long as expected.