Not to say "success" is only measured by your income, but I learned a ton about the retail world: financing, due diligence, a bit of leasing and PM, etc because I worked for a retail operator.  

Since when investment success is measured by the level of leverage one uses to invest?

Very costly if you ignore a septic tank and don’t have preventive measures in place with your PM to clean them out 3 to 5 years. 

I'm not sure how to measure the upside on rent.

Always look for preventative measures that avoid catastrophe.

I have been warned about grease and grime in kitchens in apartments because of the traditional foods immigrants cook that require extreme cleaning measures during tenant turnovers with these people

In construction there's a saying "measure twice, cut once", it's good advice in a multitude of situations. 

I learned the hard way that if you don't take measures like that, then if you do have to go to court a judge won't give you anything.  

Interior design/staging is probably the single most important thing you can do to actually sell a home, because it so dictates how that buyer feels when they walk through.As for the issue of using standard measures, I would stay ceiling height is a big one.

You need a cabinet that is wider than the sink.Check out the Kohler Whitehaven tall apron sink. 1) a 36" sink fits a 36" cabinet. 2) It is sel;f rimming which mean you do not need to be a master carpenter to nicely cut the sink into the cabinet. http://www.us.kohler.com/us/Whitehaven-Kitchen-Sin...You would have to be very careful with your measuring but this reclaimed 3" could allow you to put a standard 24" dishwasher to the left of the sink.  18" are the same or more expensive as a 24".