In general if I run out of money for anything I want I always feel terrible, it's not usually a problem when it comes to Diapers though as fortunately I dont have Incontinence, so I enjoy them at my own pace, which is usually 2 or 3 on the weekend.
Essentially if I can order at least a case I am set for months, at one time I order probably 4 or 5 cases from XPMedical (this was probably a good 4 or 5 years ago, when they still had the old owner and the Medical Style diapers were a bit better than they are today), that order lasted me a few years.