Condo Heloc could be difficult with recently being listed for sale..check in with @Joseph Chiofalo he's a South FLA based lender and they have DSCR and alternative income bank statement second position programs..they also do mixed use and 5+ units commercial lending. 

Depending on if you use a DACR loan or other alternative financing the LLC might be required.

From maintaining Winter and Summer temperatures to deposit alternatives, etc.

., you may consider conditionally approving with a higher security deposit (or alternatively, use an insurance policy - "fee in lieu of deposit"), first and last month's rent.

@Kevin Kim I’ve had great success with tenants of alternative lifestyles from my own.

So if you wanted to invest in alternative assets using your existing Roth IRA you'd have to do so in a SDIRA.   

They have been up-front and honest with me about a 1031 issue i had and even offered me alternatives / an out when timing got sideways. 

Alternatively there are several 'plug & play' national brokerage that allow you to work with a variety of up to 100+ banks/lenders but the challenge is again sort of being on your own when it comes to processing, disclosing and closing.

Alternative income options are available but will reduce the maximum loan to value. 

In the United States in 2024, mortgage rates are generally tied to the overall bond market, as most residential mortgages, including conventional qualifying mortgages for owner-occupants, residential investment mortgages (DSCR loans), and even other alternative residential mortgages (non-QM), are securitized.