I would also investigate what protections title insurance might provide in a situation like this.

This is all very preliminary and haven't yet approached family because I believe they still want to have some involvement and thinking through how best to position this to make a deal happen.I know the above leaves out many details, but I'm looking for advice on ways to structure a deal that would give my family an opportunity to sell the land, remain somewhat involved/retain some equity, etc.

Hi Shankar,  Give me a call and I can help you investigate it. 

They probably intended to tack on the fee in your preliminary closing docs and forgot until someone was reviewing the docs post-closing.

We've been doing this for a while so we run some preliminary numbers on our own to establish a budget (It's the beginning of our scope of work)3.

But if not they will keep an eye out and if they get more complaints they will begin to investigate.

Ask them if there are any lien's on projects they contracted on, investigate if so. 

So that may be something you want to investigate.

Upon further investigation, there were no supply lines or waste lines under the house.  3/2 1400 square feet.  

Most agents will find a way to make you go away so they aren't investigated by the State.