Thank you for your thoughts. I have been renovating a house and know it from top to bottom and I know of no way a possum or racoon could make it into the house. I'm also familiar with the mess a racoon can make when it gets into a house. I've locked on in my garage before (on accident) and it knocked tons of things off the shelves. There is also food sitting on a table about six feet away from the scat and there isn't any that has been ransacked by a wild animal.
As I mentioned in my post it was located on a "ledge" which I'm diagramming below. As you can see, this area doesn't seem very accessible for a anything but the smallest of animals... but then the size of the scat seems to say otherwise.
I haven't seen any further evidence of critters so I'll chock it up as a mystery on how it got there and hope I don't stumble across any more.
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˖˖"ledge"˖˖˖└───────┐
˖˖3" wide˖˖˖˖˖˖˖˖˖˖˖│
┌──────────┐SCAT˖˖˖˖│ <- Area is about 1.5" wide and 1.5" high
│˖˖˖˖˖˖˖˖˖˖│HERE˖˖˖˖│
│˖˖˖˖˖˖˖˖˖˖└────────┘
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