Huntsville, AL Investor --- Newbie

[Jeremiah House]

Greetings everyone! I am a new investor who has 1 property currently for 10 years. My business partner and I are about to refinance this property and get equity out to start purchasing more properties and accelerate our growth. I'm looking for any and all suggestions you can offer---but specifically I would like help on the following:

1. 1) We are currently on a 15yr investment loan at 3.325. We have been quoted another 15yr at 3.125 with $55k out. Should we do this? Or should we move to a 30yr that increases our cashflow but at a higher rate (currently we've been quoted at 4.125% for 30yr) with the $55k. I'm really unsure of how to balance cashflow vs lower interest rates. 

1. 2) We plan on taking this $55k and leveraging it into being able to buy $275k - $366k (15-20% downpayment of the $55k) worth of loans to purchase properties. Should we just find properties and go to banks as we find them to close (closing costs on each property) or should we seek out a line of credit or something to pay cash for upfront quickly and then let banks put those houses as collateral as we purchase these houses. I'm really seeking out the best ways to finance the purchase of these houses without putting a lot of cash on the table. Best practices you use is very much appreciated.

Thank you for your time and help.