As a Certified Residential Appraiser myself – who has inspected literally hundreds of Tacoma-area properties – I can tell you that many of these anxieties can be easily addressed with proper preparation, realistic expectations, and of course basic manners. To sum up:

1. Thou shalt clean up after your dog. I can count on one hand how many times I have inspected houses where the owners had dogs, where they had cleaned up after them in the yard. Remove the land mines!
2. Thou shalt not ask “so how much is it worth?” The appraiser works for the lender, and the appraisal report is for them and the borrower. If an appraiser shows an unintended party the appraisal report or shares key findings, that is a violation of the Uniform Standards of Professional Appraisal Practice and could get the appraiser’s license suspended. So don’t put your appraiser in that awkward position.
3. Thou shalt not follow the appraiser around everywhere. Ever attend an open house and have that annoying Realtor follow you around everywhere? Not fun, is it? Now pair that with balancing this inspection with several deadlines, and having to precisely account for the measurement, materials and condition of the property. Give the professional some space to do his or her job.
4. Thou shalt provide proof of upgrades, remodeling, permits, or other changes to the home. This is courteous, responsible, and helps the appraiser help you by proving to the lender your home may have superior condition compared to other properties.
5. Thou shalt take care of basic pre-listing items. Strap your water heater. Make sure there are smoke and CO detectors installed in the house. If the house is vacant, make sure utilities are operational. Make sure your appraiser can access the attic and crawl spaces. If you accept FHA, VA, or USDA offers on a home built before 1978, give the house a new cover of paint just to make sure there are no chipped or peeling sections on the siding (#1 reason for mandatory work orders due to federal regulations). Save everyone time and money and do it right the first time.
6. Thou shalt provide comps when appropriate. This is especially helpful if you are selling or refinancing a rental property, and know the rental amounts or lease terms of the competing properties.
7. Thou shalt not lie about easily verifiable things. No, you can’t count unfinished basement square footage as living space. In fact, lenders require appraisers to only consider above-ground living areas as the gross living area. So when listing your home, be ethical and transparent about basic features of the property. It’s not like these details can’t be discovered anyway when reviewing public records – or inspecting the home.
8. Thou shalt not debate me with Zillow. Yes, I’m aware your Zillow report (or your Redfin report, or your tax assessor, etc.) says your house is worth a particular amount. But can the computers behind those valuations see the inside of your house? Can they see your remodeled kitchen, or your weird floor layout? Can they really understand the difference between a western-facing 180 degree view vs. a northern-facing partial view of the same mountain range? Automated valuation has its uses, and is a great starting point. But there’s no replacement for human judgment, because residential real estate decisions are emotional and not commodified.
9. Thou shalt be patient. Your appraiser is most likely underpaid, working on ridiculous deadlines, and subject to litigation or crushing disciplinary measures for getting anything wrong – or losing business due to providing a conclusion someone doesn’t like. By all means, provide helpful information. But exercising some common courtesy on top of that will really help assure smoother sailing for your appraisal.