Many years later I stumble across bigger pockets and saw people talking about refinancing to acquire more properties.  

Refinancing your rent property to pay down your primary mortgage is a really bad idea.   

Doesn't mean that refinancing may be a better option.

There are some lenders who can avoid the seasoning requirements, though make sure you find this out from your re-financing lender.I am also an investor in the KC area, so feel free to reach out if you need any contacts for hard money lenders or re-financing lenders.

My second question is that I am also planning on refinancing my primary residence since interest rates have dropped.

I know that most banks want you to have the loan seasoned 6-12 months before refinancing but I just found another deal in Texas I need to get that cash for. 

If it might take forever to sell then renting it out and later refinancing doesn't look like a bad Idea.

When it comes to the refinancing, I know I have heard in a Bigger Pockets pod cast at some point them mentioning using either local or large banks.

But please help me understand what are the pros and cons of using my own primary residence to refinance and use the money from my refinancing to start buying BRRRR properties. 

This can be done by selling or refinancing.