The 10% is good for regular maintenance but when the roof, the HVAC or the plumbing goes you had better have some capital reserves.

@Bob Bowling, how would you describe your tone in the following post?

Just always ensure the property fits your strategy and meets your standard baseline criteria (roof, mechanicals, bones, neighborhood, interior, rental market of area, and desired CAP.) 

You're going to want to look at the expected life on the major systems...plumbing, electrical, HVAC, roof, etc. 

Lately, the 50K, 60-65K three-units I've come across are in higher tax areas (around $3800 annually) AND they need substantial rehab, like a total roof replacement.

@Rob Randle You're going to need to be a little more realistic about your LTV amounts, because you're not likely to get anyone to loan you 100% of the purchase price. 

Never been updated cosmetically.  3 year old 30 year roof, 5 year old central AC units, 2 year old appliances and hotwater heaters.  

Also, I recall having a DSS tenant in one of my properties in up state NY.They where refugees from Ghana I believe, these folks where obsessed with house and looked after it to extreme lengths.Maybe a similar strategy could be implemented of renting to refugees who would actually appreciate a roof over their head and opportunity for a better life.Just my opinion.Thanks

Also, meeting you face to face will show them that you are serious, the tone of your voice will determine if the sale going to take place or not.  

We maintain the systems in the home and water drainage needs, such as cleaning the gutters and keeping the roof in good shape.