Resale is not as vital as cash flow because I'm in it for the long haul. 

If for title company, you'll need full certificate, not the informational-only version with redacted data that many state bureau of vital statistics offer.

I think that was vital to the survival of our first property. 

Networking is vital & I believe all of these things will make me a very savvy investor.

My state has laws that make owner responsible for keeping the home habitable and making sure maintenance/repairs are handled in a timely manner.

One person mentioned they are not employees, true, but they ARE a vital part of your overall business chain.

Make sure that you don't make it a habit.  

IF they know of a violation, they might note it in their appraisal and depending on how persnickety the lender is, that could be a PITA but unlikely.If the municipality does a code check to issue a certificate of occupancy/habitability before closing, THAT could potentially throw you off.  

Steven Covey (The 7 Habits of Highly Effective People).

Just like me they have discovered it is a good habit to acquire.