What method of marketing got you your first phone call? 

I know that you can do the brrrr method if you are renting out and refi-ing on a sfh.

That method seems to be a little more complicated to me, however, i'm willing to give it a shot if that's what will reel in the best results.

My name is Amitpal (Amit) and I have been looking into different methods of real estate investing.

I have 20 acquisition methods including Sheriff Sales, Tax Sales, Foreclosures, Auctions, FSBO, word of mouth, letter solicitation, REOs, government agencies (bought first house from Highway Department see BP Podcast #82), and Probates. 

whenever you're driving somewhere or performing mundane tasks at home - https://www.biggerpockets.com/podcastStart examining your local market - get set up with a search that shows you all of the properties for sale in your area.Once you start to feel comfortable with the methods and terms used in REI, start to network with other investors in your area or on BP.  

I currently own two properties which I have been renting out for some time and I want to keep getting more properties so that I can keep doing BRRR method but I came across a house that its buyer offers a special warranty deed instead of a general one as all of you may know what each offers and everything else about them.

Any updated 2017 advice you could give me for using this method?

For you first few deals I'd recommend you use the assignment method it is very simple and there is an assignment clause in standard forms once you get good you can start using the double close method.

This is an unusually good place to make money if you are methodical and somewhat consistent.