Is there any advice you'd give me on our particular situation:Husband and I are 50-something "millionaire next door" types with no debts and significant savings.

@Paul Kubin Take this advice with a grain of salt. 

Any recommendations or advice on making this switch?

I dont have the full purchase price of this 4plex to invest though, so I would have to finance half to 2/3 which seems like a stumbling block. i can still make the numbers work, but at a much lesser monthly profit i suppose. i also dont have the w2 income to support 2 mortgages (counting the one i have on my house), so i assume any bank would have to count the existing leases towards my income which i understand is possibleI guess I was wondering about advice, or red flags, anything, on this specific deal.

Any advice or personal experiences you could share would be greatly appreciated!

What advice and guidance can you share with first-time home buyers?

I'm open to any and all advice out there and would enjoy conversating with people that have experienced success and failures along the way.Thank you all for your time and interest

@Angela Costa you should research working with a financial advisor as @Jeff Nash is stating no one on the forum can provide comprehensive planning and personalized advice you need to work with a real financial professional.  

You were right to bring it to the title insurance company.My advice: find a kick (rear) real estate lawyer to investigate whether (s)he'd take it up as a case AGAINST THE TITLE CO for you.

I'm here to help with insights or advice based on my experience.