Thats the best time to inspect is when its raining in my opinion.

I carry a big arse umbrella and get after it. Carry some shoe covers and a TYVEK suit if necessary.

Charge a bit more for the condition. I've never had a client complain. They have been happy to find out that there was several water penetrations found that may not have been observed on a sunny day.

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I predict future happiness for Americans if they can prevent the government from wasting the labors of the people under the pretense of taking care of them.
Thomas Jefferson