Growing buy and holds quicker

[Tom Vanderlinden]

I have a duplex and two single family homes right now. I purchased the duplex and my first house with owner occupied financing and one house as a straight rental. I would like to acquire more rentals quicker and keep buying more and more every year, but I don't want to keep saving 25% because that takes too long. I know you can get a line of credit from a commercial lender, which I may look into this year, but I've only been doing for a year and not sure they'd give me much credit. And I've heard the terms aren't very favorable, but I'm open to that. 

What are ideas you all have for quicker expansion? I hear of people who double their number of doors every year and I want to do that! Any input or experience would be appreciated, thank you!