Without a POA it takes some time but it is totally doable. 

Inheriting a bunch of property without a property management strategy in place can be stressful, but it's doable.

That was doable before the last recession but I think it will be tough today.

That's more doable in terms of the numbers but there are a lot of "if's" before we finally get a payday.

Not possible with SFH investing but doable with multi units.

My initial goal will be to secure an initial RE investment portfolio that will net a minimum of 2500 a month in free cash flow above the mortgage/repair/vacancies/capex/prop mgmt fees (With 300k of cash/1.5m of loans I think this is doable). 

But if you're looking all or mostly cash and desire a strong tenant with a corporate as opposed to site or franchisee guarantee, with a 20 year lease remaining, 5% is not only doable but maybe a little low.

I've written out a hypothetical deal below in which I use the BRRR method to purchase, renovate, rent and refinance a deal where I'm all in at 60% LTV and then use the 40% equity to purchase a note with the sole purpose of increasing ROI and to hedge slightly against vacancy expenses.After running the numbers I realize it's not possible with the entire 40% due to banks lending on 80% LTV max, but looks like it's doable with only 20% equity as well.This is just a theory of a possible strategy.

My question is if this is at all practical, doable, realistic, or even legal?

Yes, this is very doable if you have equity in the residence that the line of credit is on.