Any advice on how/where to get discounted gift cards without the fear of receiving a bogus card?

No credit cards or non-RE loans of any kind. 

welcome @Kharhak Singhdont worry about your age by the time you are 30 there will be no need to work anymore if you play your cards right read,listen to the podcasts,ask lots of questions then get out there and learn your market i wish i would have started at your age

All credit cards and I'd be cautious of someone living beyond their means without a good explanation.Interesting that payments started in June.

I just sent out a post card mailing, and am scrubbing a list to start cold calling. 

I'm trying to increase my spending on my US credit cards to get extra airmiles.

The 3-day session has a few nuggets of good info sprinkled in here and there, but is ultimately designed to get you to sign up for "advanced training" to the tune of about $9k per course, or a $40k "special offer" on a bundle of courses.See this thread: https://www.biggerpockets.com/forums/79/topics/185...The afternoon of day 2 focuses on how to manipulate your credit score by raising your credit card limits, and the homework for day 2 is to see how high you can get your credit card limits raised. 

, credit cards (shows poor money management), auto loans (if they won't pay their car bill, knowing that the car can be easily repossessed, then I'm less confident they'll pay their rent), etc.You don't say what type of accounts these applicants have in collections, but the fact that they pay their student loans "promptly", always paid their previous landlords on time, and their income "more than meets your requirements" are all very good signs.

I've read a few blogs regarding using credit cards to fix and flip properties.

Second is all of your recurring monthly debt payments (PITI, auto loans, student loans, minimum credit card payments, etc.) divided by your monthly income.So, as an example (specific numbers would come from your lender): a lender may allow a maximum 33% for the first DTI calculation and maximum 45% for the second DTI calculation, and they will require that you are within both ranges for both ratios.