Welcome to sailnet. I would highly recommend you read the SPECIAL INTEREST thread sticky in the boat buying forum, as it requires full disclosure by marine industry people when they post here.
As for rigging, please note, I don't recommend going aloft. I wouldn't go aloft on a strange boat, much less recommend any one do so. I do recommend taking photos of the rigging from deck level. The detail in a good digital photo, especially with a longer lens, is amazing nowadays.
I do carry a multitool pretty much 99.8% of the time, and don't see a problem with carrying one. I do recommend you ask before tapping the deck with a hammer or poking wooden backing blocks or bulkheads with an awl.
I disagree about the utility of a moisture meter. After a bit of use, you can learn how to use one well enough to determine if the deck has substantial core problems or not.
As for posting links to your website. You need to have 10 posts to post links, and be careful regarding posting links to your website, as if they are seen as trying to drum up business... you'll get nuked.
As a surveyor (SAMS and NAMS certified - 10 yrs and over 1000 boats) I applaud the general spirit of these tips. I think it is very smart to give a boat a very careful personal inspection before entering into a sales contract and hiring a surveyor. I really don't enjoy taking money for giving clients bad news about a boat that they could have seen for themselves.
Most of yacht surveying is not "rocket science" or fancy meters but is simply careful observation. Often the first indication of a poorly maintained boat is the dock lines, which you can observe without even boarding. If they are old, sun-rotted, chafed, or inadequate it is often a sign that maintenance elsewhere is neglected.
I agree with the suggestion that you take and use a flashlight. It is a simple tool that, in the hands of a buyer, will strike terror in some brokers and sellers - don't look at a boat without one. Use it to look in all the accessible but dark places. Anyone can see dirt, debris, rust, messy wiring, etc.
A digital camera is also another good tool. In addition to the obvious photos, you can hold it in inaccessible places and snap pictures that you can then study. (Always put the strap around your wrist first - a lesson I learned by sad experience.)
However, although I have and use one, I think that a moisture meter is probably not so useful - unless you have a good deal of experience with it. They do not measure moisture - they measure the electrical conductivity in a region around the sensor. That can be affected by many things other than moisture.
Moisture in fiberglass boats and blistering are also complex issues depending on construction, age, and location of the boat (New England is different from Florida) that I won't get into here. You do need to get good advice from someone with a lot of first hand experience in your area (and no high-dollar repairs to sell).
I also have a different opinion about the appearance of the oil in a diesel engine. The oil in a diesel will become black in just a few hours running. This is not necessarily a sign of poor maintenance (except if the boat is laid up for storage with old oil). If I see completely clean clear oil, I am concerned that the oil was just changed prior to the inspection to hide evidence of fuel dilution (smell) or water emulsion (cloudy, creamy color). An oil analysis in conjunction with the survey can sometimes be useful, but will not find anything if the oil is new.
I also would also leave the multi-tool, screwdrivers, hammers , and awl in the car. Most hull surveyors do not disassemble equipment. If it appears useful, I will have a yard or mechanic do the disassembly while I observe. If a potential buyer with unknown skills and intentions showed up at my boat with screwdrivers, wrenches, hammers and awls, I would not let him aboard.
As a matter of liability, I also don't let anyone other than a qualified and insured rigger go aloft on my boat. (There was an interesting case a few years ago where a halyard parted during an inspection, and a surveyor fell on top of the broker.) A good surveyor, mechanic, or rigger has insurance to cover his liability for damage or injury during the inspection - Do you?
However, the rig is an important part of a sailboat, and there is a lot that you should be able to see without special tools or going up the mast. A careful look at rigging terminals at deck level will often reveal swage cracking (a little magnifier helps).
Failed chainplates are probably the major cause of dismastings. Are the chainplates easy to see? or buried? Are there drips of rust staining below decks, distorted bolts, cracked sealant or other evidence of movement?
For photos of some of the evidence you can look for in the way of rig problems, you could check out the article on my web site. (Unfortunately I am not authorized to post a link here - (edited SD).
Although, I may have some differences of opinion on details, I agree fully with sailingdog on the fundamental issue - do your homework and look carefully and in depth at any boat you are considering for purchase.