See the related page here for basic elements of service provider determinations & here for home inspector questions. If you're my client, ask me for my spreadsheet of WDI/moisture inspectors if you want to choose one yourself. In it I have answers to many of the below questions already for a number of inspectors.
In the real estate business, not being thorough can cost you, whether you're an agent or a buyer depending on an agent who isn't thorough. As an agent myself, I like to keep a spreadsheet of wood-destroying insect (termite)/moisture companies that I work with, including their contact info, costs, reviews, and a number of other important pieces of information. My business is one where I constantly seek to grow as well, so often with some of the spreadsheets I develop, I'll add completely new columns/rows over time as I find more and more information that is important to note. In the past 24 hrs, I just added some more to my termite/moisture recommendations spreadsheet. In some cases, the experience can teach you even more than the classroom, and I don't know of a classroom where all of the information below is taught.
Direct questions buyers and agents can ask the wood-destroying insect/moisture inspection companies if the buyer's agent representing you doesn't already know & if your buyer's agent can't fill in gaps (i.e. providing a camera on a pole like I have with a short/skinny termite/moisture inspector before, who didn't have the equipment necessary to inspect without cutting a hole in ductwork and repair the ductwork after the inspection):
1. Do you perform wood-destroying insect & wood destroying organism inspections?
2. Do they do estimates on woodwork repairs directly?
If so, is it a separate company or a separate inspector that comes in?
If a separate company or a separate inspector, what kind of turnaround time does that require for 2nd inspection & report?
What class of contractor is your company or the company you typically work with? (Class A will typically do better work than Class B or C, though typically more expensive)
Do you allow me to hire any contractor to perform the woodwork, or only you/your contractor of choice in order to produce a clear letter(s)?
3. What is your coverage area?
4. When would you be available for inspection at (insert address)? (this timing may vary based on location, attic access, crawl space, and other factors)
5. How long between the inspection & report?
6. Do you have droids with cameras, cameras on poles, or any other means of accessing otherwise inaccessible areas?
7. Are you able to send a small/skinny inspector?
8. (if applicable) Will your company traverse areas of attic where there is no floor? If not, will they utilize other resources (i.e. an extension pole/camera/light) to explore those areas?
9. What is the cost of the inspection? (if applicable) Any additional cost for additional detached structures? How do you handle detached structure issues, such as a wooden shed located in standing water? (I was surprised to find an example where 1 wood-destroying insect/organism company didn't flag a wooden shed for being located directly in a significant puddle of standing water)
In some cases, the above questions won't be able to be answered directly. For instance, an inspector might say that a report will likely come on one day, but if the job is more than the inspector can handle, his superior may need to come in to provide an estimate, which could add more time to the equation.
Factors that your real estate agent should note or that you might be able to find out about in reviews not covered above that the termite/moisture company might not respond to accurately:
How do your prices compare to that of other inspectors in the area?
How does the quality of your work compare to other inspectors in the area?
How knowledgeable is a company compared to other inspectors in the area? One important factor here is how long they have been in business, though sometimes a company/inspector with 10 years of experience could be more knowledgeable than a company/inspector with 30 years of experience. Sometimes a more knowledgeable company can find cheaper effective solutions than a less knowledgeable company.
How honest is the company? For instance, if they are not honest and perform woodwork themselves, they could require high-cost work that they would do themselves without allowing another company to do it, while a more honest company/inspector wouldn't do that to you.