I would recommend fixing it and then determining whether or not to sell based on cash flow and profit after the sale.

Last August a decent pre-foreclosure opportunity came available on the MLS and my agent took us to see the home and submitted two offers below asking that were too low for the seller at the time.Apparently the seller was able to avoid foreclosure and the home delisted after it didn’t sale.

They said they'd accept a 6 month term instead, but they're not being very forthcoming about what their sales record has been (I asked for the last 12 months just to get an idea, but they ignored the question :( ) and I'm getting a not-so-great feeling about working with them....The home is 2-stories, attached garage, 4bd 3ba, 2269 sqft and sits on a corner lot with a huge backyard (lot is approx .13 acres or 5662.8 sqft).

BTW: most owners that have hired a PMC, don't want to speak with you, much less meet with you in person to hear a hyped-up sales pitch.Also, you want to do rental arbitrage - so, you will need to be properly licensed to manage properties you do not own as required by your state & local laws.- why would an owner want to do business with someone NOT properly licensed?

A good local agent should be able to help with some of those updates needed for the exit sale. 

I found this deal listed for sale on LoopNet.

BUT I have also heard that it could trigger a due on sales clause, bringing the note fully due at any moment.

There are several duplexes out there for sale and if you do it right, it can be financially beneficial for you.  

You're supposed to have a license in every state if you are representing either a buyer or a seller in a real estate transaction, or acting as an intermediary in the sale of real estate.

But if it’s a sale, some buyers might be okay with a few unfinished details, especially if you disclose them upfront.