This will be very difficult to get an approval, unless there are mitigating circumstance, especially given that you want to move from a SFR to a Duplex.

Not to be pessimistic but just to to ensure that a property works for me under less than ideal circumstances  

My suspicion is that you've "paid" for any unforeseen labour or material spikes as the builder has worked in a cushion for this in their sale price. 

@Kenneth Gore yes the lender should be able to do a change of circumstance and structure the deal as a seller credit versus a price reduction

But There is a safe harbor from the IRS at 2 years under certain circumstances.  

She was even able to secure that investor to work with us under such unexpected circumstances. 99/100 agents would not have been able to do that.

@Eric Hempler not sure what course you are following, but if you find someone willing to make a private loan for 4%, let me know, I will offer them double.We normally accept and make private loans in the 10-15% range (sometimes even higher, depending on the circumstance). 1-2 points upfront and 10-12% is the average for private money or "hard money" loans in our market.

That was a pretty special soup of circumstances.

The current language reads as if we're automatically required, even if our circumstances change to accept any offer if it meets the listing price, conditions, etc. 

And depending upon the facts and circumstances of you and your husband's sources of income, you may be able to treat the loss as ordinary, non-passive.