1a) Lenders say i shouldn't fear the interest rates as a refinancing could be done fairly easily.

I am in the process of refinancing my building and getting a line of credit.

Once the property is up and running, then many lenders will want it to be seasoned before refinancing. 

I instantly cashout refinanced my first home and pocketed about $20,000.

I’m refinancing the mortgage and the loan is in my name.

Example:  you purchase the property for $400k with 80% loan to the value/ purchase price. so the loan is $320k and the 80k is the down payment you had to put as the remaining 20%.After 2 years the  house is gone up in value to $500k, now you can go to different bank and ask them to give you 80% of the new value of $500k. 80% of 500k is $400k. so the new Bank say yes to refinancing the existing loan to new loan of $400k.  

Do you think i would be better buying the first house with cash and then refinancing it.

Have your investor  be a lender and pay a higher rate until the building can be refinanced(6-12 months).  

I was thinking of refinancing and cashing as much money out and going back to 30 years.

I'm not to the point of leaving my day job yet, but am curious about refinancing when I get to that point.