I have been an expert witness in a claim against an inspector. It is true, both sides of counsel will rip testimony to shreds. The key I learned from that experience is... It didn't matter about the phrase used (Serviceable, functional Etc.) that is too big of a pissing match for someone to sue you. What is important, something that should have been reported, but wasn't. Now you got a problem. Inspect thoroughly and report what was observed. If something is as you would expect, describe it, if it wasn't, describe that. Supporting pictures are also a big plus even if they are not included in the report.