You hope either (1) neither lender finds out and or (2) neither lender decides to take action if they find out.Second, you make up the difference in equity with either (1)cash (2) 2nd mortgage loan with the owner with less equity giving to owner with more equity and/or (3) trading something else of value, such as another property, car, RV, etc. 

I have a $115 loan at 2.25% on a 15 year note. The home is valued around $300k. I’m tempted to do a cash out refi. I can cash out refi $100k to a 30 year at 7% but lose cash flow and break even. I want to reinvest the...

I wouldn't consider it until you have at least $1 million in equity, and even then there are other ways to protect yourself.What you do need is a solid partnership agreement.

each property has 100k in equity.

If you have 200k in equity and you are cash flowing 14k per year, that is a 7% return on equity.

Some have more than $1 million in equity while others have less.4.

Our current residents we still owe about $104,000, we have about $280,000 in equity.

Some have more than $1 million in equity while others have less.4.

Cash flowing and approximate gain of $80k in equity.

If not worse.The difference is negligible in your position, holding over 5M in equity, your time is better used elsewhere.