It seems like since I am a grandchild and not a child most of what the q&a’s do not apply to me.

Your situation does not seem to qualify for the tax base tfr.

It’s tough finding information on how it applies to multi family properties.I’ve also reached out to a few lenders and it seems 15% down is the minimum for a duplex unless it’s FHA.

In my area, I've found only one company that seems to deal with this regularly, but they don't respond to emails very quickly.

Your process seems like a good way to determine cash flow / potential of an investment property, if you have a realtor you can have them pull rental comps for a decent picture of the rental markert as well. 

When I went into the house, it didn't immediately seem like anyone had been in the house.

Seller is out of town and seems motivated to be done with it.

From their website: "Have you been dreaming of becoming an author, but an entire book seems daunting?

I thought this seemed like a pretty solid way to get some cashflow and roll it into eventually owning Airbnbs and or long term rentals.

He seems a straight shooter and has a good track record.