The absolute first thing I would do is make sure the payment plan reports to the credit bureaus monthly because you're starting off and, most likely, want the good credit marks. Some places don't report monthly, ex: BillMeLater from eBay won't report anything good, they only report if you're late. So a few months or years down the road, you'll have the exact same credit score after you pay off the MacBook.
When you fill out the application you have to at least put yourself, and adding your parents as joint would improve your chances if their credit is good. If they have bad credit it could decrease your chances of approval. You do not just want to put your parents as well, that would be illegal, and it's not going to help you any.
I'd sit down with your parents and have a talk. What I would propose to my parents is: 1) You're going to apply with RBS for the loan by yourself 2) If you get the loan your parents make you a personal loan for the same amount, you take that money and put it in a savings account and interest gained is paid back to them. 3) You pay RBS. 4) When RBS is paid you return the loan to your parents with interest and take them out to a nice dinner. --- Now what's the point of the parents loan to you? If, for whatever reason, you can not pay RBS then you take the personal loan from them, you pay off the RBS balance immediately, and you start paying your parents. This is simply because your parents don't report late payments to the credit bureaus. --- I know some parents will not do this, they might not be able to or for whatever reason don't want to. If that's the case then I'd either go it alone or perhaps co-sign.
