HELOCs and HELOANs do exist for rental, but with prime so high and secondary tier of LLPAs associated with these programs you’ll be above 10-11% all day.

Combining primary mortgages (on a subject acquisition) with a fixed second mortgage (against another property) can reduce the loan to value (LTV) on the qualifying mortgage; which should provide lower interest rates and make the offer to purchase more competitive (since there is a larger down payment.) 

You are only looking for a 6% return...you can almost hit that with current High Yield Savings accounts or CD's. 

@Todd Knudson high yield savings account.

If you can't keep control of your personal finances, you are highly unlikely to succeed in real estate investing.

I would highly recommend FB marketplace and also joining local FB real estate, rental, and leasing groups. 

If one is a CAT 5 and hits lower Florida at high tide with 20ft+ storm surge goes into the Gulf restrenghthens and hits somewhere from Florida to Texas again at high tide with a Katrina size storm surge of 28ft it is an issue.

If you're in an area with high demand on contractors you'll probably pay a higher per sf price than in some other parts of the country for a new build. 

If you can't keep control of your personal finances, you are highly unlikely to succeed in real estate investing.

You will be surprised how high they are going.