Question about Pack Purchases

So, I’ve heard that we can re-purchase a car pack for a second time through the Gaijin store. I’ve never tried it before, and was wondering if anyone could give me a heads up of what I need to do. Xmas is coming up and I plan on re-purchasing the 4 Horseman pack so I can load up on the coinage and, then, do something real stupid with it all.


Never tried it someone once told me it was before you synced up to steam but never looked into it.