While we are both in Central Florida currently, and looking to partner on our first deal, we both have roots up north.

Don't do that when you spray the leaves as the chemical won't get to the roots and kill the plant if you cut the vine then. 

The street was lined with huge CITY OWNED trees so we know the old ceramic laterals were being compromised with tree roots.

I called a plumber.....they came out to fix it.....Now everyone is happy.Since you're in the East Bay like me, I would suggest you have your property manager in Cleveland give the tenant 24 hour notice that they are going to come into the property to see if they can figure out what's going on......They may find or hear something that may not intially be visible but if they run some water faucets and or flush the toilets and water keeps dripping or running afterwards you can start to get to the root of the problem. 

AirBnB:Got a 5 star review that gave 3 stars for cleanliness because of “Soap scum on the shower curtain” I saw it coming a million miles away and gave the guest 4 stars with 2 stars for Communication because she was silent and cocky due to her 7 other glowing 5 star reviews.

I picked "UpTown Detailing" instead of anything with either my name or the common wash/soap/shine/etc references.

But you still need to fix the root cause of why it is in the attic in the first place.

Any tree(roots) in the path of sewer line?

I'm concerned that it might be tree roots growing into the pipe.

Some of the things we put out were local soaps, bbq seasoning (Omaha steaks), and local candy.