Take photos of the property, it's condition, etc.

It's needlessly complex and expensive and time-consuming, but doable.Strategically, I think there's money to be made by doing exactly what you're thinking - by making the structures individually salable, you're unlocking value. 

Pay for pro photos.

Between the photos he sent of this property on a previous walkthrough with another client of his and photos from the property inspection, I felt confident on the condition and knew what work needed to be done.

Going from photos, this will be more than what he quoted in repairs unless the interiors are in pretty good shape? 

I do the photos and listing and use the system I already have in place to screen tenants.

When I do get water turned on, I tell them to just unlock the valve and I'll turn it on myself when I'm onsite in case there's a leak.

For a great presentation, create a PDF with property details, photos, comps used to support your ARV, description of what needs to be done on rehab/repairs, numbers breakdown showing how you arrived at the profit number for the investor, etc.

I've occasionally asked a friend to drive by (ex, when the roof had to be replaced) for me and snap a photo.

You can also do the obvious things like make sure it's staged well and take high quality professional photos, but if the price is off it's not even going to show up in buyers' searches.