Potential properties that pay all utilities?

[Bud Dwyer]

I'm looking at buying quads here in Phoenix.  Some of the properties I look at note they pay all utilities.  When I run the numbers only paying sewer/water/trash they cash flow well.  Paying everything seems to make them only cash flow at $1k per year. 

My question is are these propertiee red flags in and of themselves?  I know I could buy the property and stop paying for utilities once the lease is up.  I just don't see the need the current landlord would need to pay them.  It makes me wonder if there is some added reason they might not disclose on the listing.

Am I being paranoid, or is this a legitimate concern?