In the USA be careful of credit offers as there was some issue a few years back. Not sure of all the details but I remember that when I was in the classifieds game that was a problem at one point. I don't know the details because I was not a credit check/card guy in that game.
To the person who said something like, "you would not abandon a 4K a month method that only took 1 hour a day" or some such thing. 4K a month is not that big money using a method like this - I did an average of 18K - 20K a month with a similar method using a different vertical and dropped it at one point. People move on to different things that make as much or more depending on what is happening in their lives.
I believe I spent less than 2 hours a day for my money and I could easily have spent just an hour and it would have been just fine.
Be smart, guys, twist this method some and don't be greedy and you can do just fine.