I have been to a few of them personally its really something and the folks that own them are under the radar and make MILLIONS.

I'm 53, married with 2 kids less than 17 years old with debt only from purchases on credit cards and my home.

If it is a credit/equity line, you could provide a lender letter that the funds are available immediately for funding - and cured any recission period. 

Here are some Key Takeaways for You to Turn Your Multifamily Real Estate Dreams Into Reality:➡️Define personal goals.

Or can you still run everything through your personal return (just want to make sure that I can deduct things such as HOA fees which I can do if it is a rental).2) If I do decide to run everything thru my personal tax return (save on LLC fees), should I at the least set up a separate bank account to track costs separately?

Quote from @Amanda Dobbs: Is there a place to find Private Investors as in one person?

The seller purchased the property to do a favor for someone and the person died.

The “buyer beware” philosophy is fine for commercial transactions, but taking “advantage” of home owners when they’re most vulnerable and lack market sophistication is something no right thinking person wants.  

If the property were owner-occupied, would I only receive credit for one rental unit's income, while the non-conforming basement income wouldn't count?

The better the rates, lenders generally want to see more experience, higher credit, occupancy and DSCR requirements.