So you might as well be a head of the game do the cash out refinance buy the next 1-2 properties and simply refinance the original mortgage as a "rate and term" which carries a lower rate.

Take ownership of your mistake and learn to do the proper due diligence recommended above😊

For active investments I advocate considering how you can diversify WITHOUT ceding your competitive advantage nor the superior profitability of the niche your in.As an example my business is running an investment fund and syndication high interest commercial mortgage loans secured by income producing real estate. 

A Mortgage Broker,Happy to connect.

Take ownership of your mistake and learn to do the proper due diligence recommended above😊

Since I had a couple million in mortgages in my personal name, I couldn’t do it.  

For the $525K property, with the low mortgage rate(you will probably never get a such low rate), it might make sense to hold onto it for now, especially if you can still sell it as a primary residence within the next three years and avoid capital gains taxes.

Specifically, I am looking at partnering with an individual who owns securities (stock and mutual funds) having them take out a line of credit against their portfolio (SBLOC) at a low interest rate, and using that to purchase properties rather than using a mortgage.

Deed restrictions tied to a mortgage can be tricky to remove, but it’s not impossible.

It gives you a list of all the assumable mortgages in your area.