The PM called her and said, "It's going to be $800 to replace the garage door opener.

Sounds like it might be doable, especially since you have already experienced what it would be like.

Here they all start with "Are you aware of any XYC.." and none of them are asking about previous repairs or issues.I understand that you are concerned, but honestly, if the water damage was resolved, the soaked parts replaced, why would it matter any longer? 

This sounds like a great property.

@Mike Terry sounds like a pretty good argument to go after the property, I think your question is more along how to value it, and account for the deferred maintenance. 

It sounds like they just sent you to a lender and builder and maybe they got a piece from each?

Sounds like a great deal/property.

Please let me know if this sounds correct.

I don't know what they are but unless there's something in the city that requires that kind of notice, it sounds excessive to me.

This sounds like you need an attorney to do this.