A good access report is specific, first-hand, and honest about what you didn’t check. That’s it — you don’t need to be thorough, you need to be accurate about a few things.
What helps most
Say what you saw, not what was advertised. “The website says step-free; the side door has two steps and the ramp was locked” is worth more than either source alone.
Be specific about the thing that decides it. Not “good access” but which entrance, how many steps, how wide the door, where the restroom is. The detail that made your day work is the one somebody else needs.
Say when you don’t know. “I didn’t check the restrooms” is genuinely useful. It stops the next person assuming your silence meant fine.
Date it if it might change. Elevators break. Construction happens. “As of last week” costs you three words and saves somebody a wasted trip.
A shape that works
Place, and when you went
Getting in — which entrance, steps, ramp gradient, door width
Inside — surfaces, seating, lighting, noise
Facilities — restrooms, changing, parking
What I didn’t check
What you don’t need to do
You don’t need to measure anything. You don’t need to cover every dimension. A single sentence — “the ramp at the north door is steep enough that I needed a push” — is a useful post.
Post these in Accessibility Tips. If it’s about somewhere with a published guide, City Guides gets it in front of the right person faster.