Lower risk, lower reward.Flipping by yourself or with a partner is more risk, more potential reward(also more potential LOSS).

Buy something that's turnkey with value-add potential.

Im hesitant because I dont want it to interfere with my ability to secure financing in the future and frankly I not interested in taking on the risk without any potential reward.1. 

In those cases, almost always better to bet on the Hawaii or california as that floor is likely going to raise.

It is unrealized cash potential when it comes to selling/cash out refi/HELOC.4.

This will get you a better idea of the potential fair market value of your home.

Minus potentially a small discount since it's an ADU?

There shouldn't be double taxation because rental real estate normally operates at a tax loss.The potential time that there will be a tax consideration is when you sell the property.However, your resident state(MN) will provide you a credit for taxes you pay to a different state.This will avoid double state taxation.In general, California state taxes are higher than Minnesota state taxes, therefore, you will be paying the higher of the two state tax rates, which is California.

I know I will find answers if I keep reading and exploring, but I have a potential deal going right now, so I need the answers sooner rather than later.1.

Lol, I bet you were having some Tennessee Champagne as Blackberry Smoke calls it... :-) Hahaha, I'm actually much more of a wine guy than whiskey or spirits.