They have various rates to choose from but I am still looking for a bank with better options.

Your budget of $600k would afford you a number of other options in the Myrtle Beach and North Myrtle Beach markets. 

I recently came across this "FHA construction to permanent Loan" option which seems almost too good to be true, so I wanted to get some input on how this works and where I might be able to find a lender.

It's a last chance option to bail out if their residence is a pit of despair.- Require renters insurance and ensure you are an "additional insured." 

I think owner occupied primary home financing can be some of the most favorable terms out there, especially with the low down payment option.

Options? 

Yes - Multifamily DSCR Loans can be a great option for this - check out this recent article posted last year on everything you need to know about Multifamily DSCR Loans (generally for properties with between 5 and 10 units) including comparison vs. traditional loan options!

lets look at renting and refinancing options 

Hey BP Family, I'd love your insight on this.I'm currently weighing two intriguing options: house-hacking a 4-plex or venturing into the realm of MTR with a single-family home or duplex, particularly for renting to travel nurses.

I too am looking at Detroit as an OOS option and would love to see your neighborhood info.