I would think most agents could do this, but again, some may not have this flexibility internally or with their carriers. 

I am seeking to find a hard lender to help complete this deal or get a conventional mortgage.

Seeking your guidance/wisdom.

And the reward on the other end is financial freedom and flexibility that allows you to support your family and your dreams without running on that RVU treadmill and feeling like taking a vacation means losing money.

Good luck Hard money is pretty flexible if its a good deal and if you have the money to pay the down payment.

We're relatively new to this and seeking our first STR property in about the $500K range using one of those 10% down loans and the cash from the original refi we did at 70% LTV. 

Even so, some of those  unfinished subdivisions are "coming back to life" as start-up builders and other developers seek to cash in on the shortage by providing new construction to those who can afford it.The housing shortage is real - has been for over a decade already.

My advice is hindsight and maybe not what you are seeking but advice for anyone else reading this post and can learn from your mistake. 

I am a beginner investor seeking to buy my first duplex.

Your residential LO advice would be accurate if seeking a traditional Fannie/Freddie loan.