New to Investment Property

[John Sable]

I bought my first duplex in August of 2021.  I pulled money out of my 401 for the 25% down (80K).  Payment is $1500/month and rents are 3K.  I bought my second Duplex in February 2022. I pulled again from my 401K for the 25% down (80K).  Payment is $1500/month and the rents are $2100.  I am looking at a 3rd duplex now about the same scenario.  I do not want to pull anymore from my 401 for the down.  I do have a year reserves on the first duplex and about 100k of equity. I have 2 questions:

1.) Shouldn't I be able to refinance the first duplex and pull 75% of the equity out for the down on this 3rd duplex?

2.) Am I making a huge mistake using some of my 401 for these first two purchases

Thanks in advance for insight, opinion and advice.