But even then, seller financing is rarely substantially better than another investment they could make (including trust deed lending, which will often be at a higher rate than seller financing)In my experience, the owners who find owner financing advantageous are at the ends of their careers and are not interested in looking for another investment (other than the usual retirement funding sorts.)

Even more so if they have to haul firewood up to the attic.

It's still possible to BRRRR now, but the deal has to be muuuccchhh better and those are just much harder to find.People are still making it work in real estate though, primarily by getting more creative and often needing to add even more value to make the numbers work.

You typically will see small banks/credit unions probably wouldn't be able to out-of-state, but otherwise any mid-size company or larger should be able to.So would Bank of America be an example of national even if I go to my local branch?

You may be safe to get non-commercial F/F adding up to 2 ADUs to a duplex even though by rule this does not qualify (in my area I have never heard of this being an issue). 

However, even in these cases, you typically leave a small amount of money in the deal and only break even before accounting for vacancy, repairs, and other expenses.

If you had a PM it would be even more. 

I saw the building has tenant and even upstairs which is direct to roof this one I got in first floor.

Even if the rental has a decent cash flow with additional flood insurance, we're still not sure we want to take on that risk as we are out-of-state investors (planning to move back to KY in the future, but not now) and we don't like that it will potentially bring down the perceived value when we try to sell it in the future.The seller has never lived there and has not provided any information on if it has flooded before or not. 

There are a variety of guideline requirements we have to consider based on the property itself or even the loan type.