And we wondered, what would be some possible benefits of going that new construction route and some trade offs?

It will provide you the benefit of offsetting your living costs, collecting rent (possibility of cash flow), and utilizing a low down payment.

Your father did you guys a solid and everyone should benefit.

If you have self-employment activity, you may be eligible for a Solo 401k which can do the same thing and offer several additional benefits. 

The more you're into it, the more you benefit from it.

So it doesn't have to be an either or choice to have benefit for you.

It's not related to my question, but maybe someone on the forum will benefit.

It would be the same case if you commented about your discovery of rockets with Elon Musk in the room:) On a serious note, the others on this thread are simply sharing depth on the subject and highlighting the fact that you COULD have done a cost seg study and it would likely have given you more tax benefit on top of what you received. 

There are tons of other benefits for 30+ day rentals too.I can handle most of the items you mentioned as well as the ongoing management.

My second post was in response to someone weighing the cost/benefit of self managing.