Advise on equity in my home

[Sean Lefort]

Hi Bigger Pockets Family!  I've been listening and following for the past 6 months and am eager as ever to start investing in real estate.  With that said I have a question that I am hoping some of the professionals or those with experience will be able to answer.

I have my primary residence in St Petersburg, FL which is an extremely hot market at the moment. I currently owe 140K on the property and its worth 475K. My goal is to build an ADU above a garage and also buy another investment property (Yes, I am zoned for and able to build the ADU). I have 30K in my bank account which I could use for a down payment as well.

My question is- what is the best way to gain access to this equity and should I use it all to build the ADU and obtain a second property or use a portion of the equity to build the ADU and use the 30K I have in the bank to obtain a second property? Is it through a cash out refi, HEL, or HELOC. My current rate is 3.6% on a 20 year loan.

I look forward to the replies!