So in this example by the OP, pretending this duplex is a 5-unit or larger, we have $11K NOI / $348K purchase price = 3.2% cap rate.

Obviously the OP has read the wrong posts, podcasts and wholesale guru crap on the internet and has delusions of being in real estate. 

@Christian Bors, the OP said the tenant lost their job.

In that topic, the OP's main problem, IMO, was he didn't research banks and their type of lending.

If anyone has experience with these types of properties, I would love to hear what range of op-ex per unit or op-ex ratios you typically see, or any additional resources you could point me to.

If you can find some coin-op machines, that could help...

As of now I'm looking in the Yonkers/White Plains area for a co-op that allows subletting.

I would think you helped the OP greatly.  

Joe isn't willing to provide anything that BP members can benefit from, and recent posts aren't helping answer the OP question(s).I'll only add that for property with GSE loans, the post I made 12/27/13 is an effective way to get GSE loan benefits (low, long term rate) without issue.

I found this that might also be of interest to the OP regarding the original question http://www.biggerpockets.com/forums/48/topics/10749-newbie-from-atlanta-needs-exit-strategy-on-duped-deal