It would be nice to think it would find things like this:Stricktly speaking at a change of tenancy is a good idea anyway as it would become a good tool against rogue tenants....
... Yes, I think we've already agreed that it is probably a fairly good idea...
Kind Regards, John
https://www.diynot.com/diy/threads/why-i-hate-domestics.507103/
However everything in that picture tested ok and was in a confined space so not an obvious thing to look for.