I would assume it's not difficult at all. Given their target clientele (people who don't even have $1000-2000 to purchase a computer), they frankly can't be that picky.
Just applied for apple financing through barclay. After waiting for a few years to apply for a new credit card (which happened to be a Barclay Rewards Card) and being approved, I was worried about applying for apple financing through Barclay. My credit score was 620 but after being responsible with my Barclaycard after one billing statement (I made 2 different payments), my FICO score already increased 6 points. I know, not a lot, but a good place to start.
Anyway, back to Apple... I was worried about applying, but seeing that Christmas is a month away, I applied. I was approved for a higher credit limit than my Barclay Rewards Card and was able to buy my partner the gift he deserves, giving myself the time I need to pay for it.