So I'm trying to get to the owner before they've exhausted all their options of unsuccessfully selling on their own and start seeking agent assistance.

Pathetic. this is a pipe dream  there is more to the test than just having a fence in one spot..  

I am nearing the end of this project and it was worth every moment I spent working.I am worried about the cast iron piping that runs under the driveways, but am budgeting replacement to avoid surprises

Exhausting for sure but well worth it !

Taking care of elder dependents can be exhausting and time consuming - don't underestimate it.Can you find fewer properties that will cashflow the same or better, or were you hoping to have that 10-12 to spread the risk?

Las Vegas has very limited land resources which are quickly being exhausted.

Thank goodness it was one of those giant-sized lots so we got LOTS of practice pulling out the pipes. 

Plumbing piping, hot water heater, etcHVAC?

Slate roof (insurance company hated that, I've posted on here before), old galvanized steel or cast iron pipes that were failing piece-by-piece, old electrical with tenants complaining about tripping circuits, cracked foundations and water in the basement, and on and on. 

Dog **** on the floor,  rusting cracked pipes in the basement,  cracked foundations, leaky roofs,  you name it.