I would not recommend.

If you have resources you recommend on using OPM -- I'd love to see them!

If you are trying to make it a place of business I would recommend looking into either an SBA loan or a commercial loan, or private lending.

If not, there are multiple CPAs that commented on this post that you can reach out to or I can provide a recommendation if you'd like.

No mathematical reason to pay off low rate mortgages only to turn around and borrow at 7.25% (plus $5k and hassle of obtaining) your money back that you used to pay off your 3% or 4% loans.  

You recommend that over buying RE in SDIRA?

Normally in a spot like this, we would recommend to a client that you sell your primary residence and claim your capital gains exemption under Section 121, but you have two strikes against you: (1) you have not lived in this property long enough to qualify for that, and (2) I'm hoping you already claimed an exemption on the sale of your other primary residence a few months ago, and you can't claim Section 121 exemptions within 2 years of each other. 

What site or course do you recommend to start the Maryland Real estate sales person journey?

Recommendations would be great.

It's great to have you here.Here are some recommendations for you:Find and connect with other BP members that are in your area: http://www.biggerpockets.com/m...Set up keyword alerts to be notified of the topics that interest you: http://www.biggerpockets.com/a...Read Beginner’s Guide: http://www.biggerpockets.com/r...Check out BP Money Podcast: https://www.biggerpockets.com/..Wishing you the best