If you live in a no income tax state it is reasonable and there are plenty of choices, if you live in a high tax state like CA it doesn't matter and may actually be better to also invest in a high tax state because you get credit for taxes paid to other states on your state income taxes.However there may be better deals in states that do have taxes but you'll be fine with or without them.

It all depends on your investment plan.There is a time point you can calculate that these two choices cost the same. 

Technically no, however if you don't know what you're doing it may be beneficial to pay for one out of your own pocket, or at least someone to assist with the transaction.

Start with house hacking or condo hacking by using VA loan is the best choice.

I think purchasing a turnkey as a rental is a personal choice. 

I’m sure you will find like minded people to build relationships with that could be mutually beneficial.

For BP folks, real estate investing is the small business of choice. 

How do I structure a deal with this man that is beneficial to both of us?

Is investing in expensive beginner programs beneficial in the long run for RE?

Assuming you have a lot of equity, doing a cash-out refi can enable you to buy more properties, and assuming the new properties cash flow, yes, it could be beneficial.