But most of the other reasons are external. 

Got a freind that had 2 external backups on her desk and when someone broke into her home last month they stole the computer and both of her back ups.

With large margins (high ratios), shifts in external factors will have a smaller influence on the profitability of the business.In other words, it's the ratios that are most likely to indicate the long-term success of the business at continuing to generate profits in the face of real world situations.You're a landlord, right? 

Each app has an external webform link that you could give to the sellers if you'd like.

They make units that don't require external venting.

Adam P do you use the automated investment tool on lending place or do you hand pick all your investments?

As for R&M costs, I’ve arranged for my PM to assign ALL work to my own hand-picked, trusted contractor.

School districts can make a difference but these other external factors may not be an issue if your home comps are close in value, that will indicate similar neighborhoods.

I do have a general contractor I am comfortable with as well as a hand-picked and trained property manager.

Since that is an external issue, it seems to me the HOA should address it if they are responsible for common exteriors.