He also said the roof was leaking because one shingle needed to be replaced, but that did not explain why every room and bathrooms in the upstairs had water marks running down the walls.

Sites like FCI and Watermark Exchange have notes for sale, but the data seems very questionable. 

James,Have you checked out Watermark Exchange?

I work with RE/MAX Watermarke and I'd be happy to help you out in any way. 

This is a common practise on platforms such as FCI Exchange and Watermark.

What are your experiences with either FCI Exchange, Watermark Exchange or others?

The only thing I could find was on the Arizona Department of Realtors website; they have forms, but are watermarked and not for use unless you are a licensed realtor.

Also, set a high water mark and do not ever ever ever cross it. 

This isn't all hypothetical, in 2018 rates hit a 7 year high water mark, a non-trivial bump in the overall 40 year pattern.

Something that may work is putting watermarks on your listing photos, even if a potential renter might ignore them, the scammers won't take the chance as there are other photos to steal without that risk for them.