My overall goal is to house hack the property, but at this rate, I would have to save a significant amount per month to put around $5-6k as a down payment.

Bandon, home of one of the most highly rated public golf courses on Earth (Bandon Dunes) is also a luxury oceanfront investment location.

Our rental is paid for and has rental income of $2200 month and our primary has a mortgage of $1800 so we are currently living for free basically.we have a credit line on our rental for $275k and recently got a letter from our mortgage company offering a cash out refi on our primary of approx $300k and still be able to keep our current interest rate on the remaining balance of the mortgage which is mid 3 %.We are trying to grow our rentals and struggling to figure out the best way to do that.

Another option would be to tell them you have to make decisions based on your investors best interests.Your investing partner could be your significant other, but they don't have to know that.That way if difficult decisions have to be made in the future the frustration would be at "the investor" and not directly at you.

If so you can look into Cash Re-Fi (not as popular these days with high rates) OR look into Home Equity Loan / Home Equity Line of Credit.

Best of luck on the journey! 

An architect is your best friend during this phase.

The desire to have a second home/Airbnb property in the beautiful state offsets the modest returns we're seeing now due to higher interest rates and taxes. 

Later, once the offer is accepted, check with the 4-5 lenders on who can give me the best terms?

Best to get independent and not deal with the neighbors anyway.