But if the debt is say 50% of value - what’s the chance of the property not “covering” the debt  and your personal guarantee being enacted? 

Make sure you have funds set aside for an emergency, if you have personal debt, try to eliminate as much as possible, understand what your personal balance sheet looks like in regards to monthly cash flow and net worth.Investing in real estate is investing in a business, and you need to have a good understanding of your financial picture before you begin to buy a business.I would then focus on what niche you want to start with.  

and you can find an almost unlimited variation on risk ( from low to high leverage, both floating and fixed rate debt, from no to high skin in the game, etc).

Upfront out of pocket isn't feasible, going into debt for it doesn't make sense either.

Specifically refinancing debt/loans?

Driving them deeper into debt with claims of big money is a sad way to make a living. 

This way the property is owned by the LLC even though the borrower on the debt is you personally.

- Who carries the personal guarantee on the debt?

Here's why:With a DSCR (Debt Service Coverage Ratio) loan, you can leverage the rental income from the property—like the $4,800/month rental revenue—instead of relying on the seller's personal credit or income.

ARV is irrelevant for taxes.Then you subtract land value and depreciate the rest. Or