Visible moisture
If you notice water under a sink or near a connection, take a photo. Explain whether the area stays wet or whether it seems tied to use of a fixture.
An empty rental is a chance to follow up on problems the last tenant reported. Send Bryan your repair list and move-in date. He can discuss what a visit would cover and when he’s available.

A problem that comes and goes may not show up during your walkthrough. Bring the earlier repair notes so Bryan knows what has been reported. For example, a toilet that occasionally keeps filling is worth mentioning even if it seems fine when you visit.
Tell him when the next tenant is due to move in. You can then discuss the items you want checked and the work he has availability to handle.
Send any plumbing notes from the previous tenancy so Bryan has the background.