some people base their dump purchases by bin, which works but is very spotty as anything ''high hitting'' would have heightened security alerts. in addition, when many people use the same bin over and over again, it makes it just that much harder to get anything substantial out of the dump.
the best way is to purchase fresh bases/dumps from your target area. for example, if you are in california you do not want to buy dumps from a base in florida. now if your dump supplier is getting dumps in california and you get a dump from florida (according to bin) it's still ok as long as you are using it in a reasonable amount of time (eg 24 - 48 hours after skimming). why is this ok? because this tells you that the florida based dump has went outside of its local region. usually, this enables one to get a higher amount (if money is actually in the account) because geographic limitations are lifted.
this geographical limitation being lifted is particularly true with 201 dumps. i have seen very good results ($3k+ hits) on fresh skimmed 201 dumps from a target shopping area -- example, a 201 dump is skimmed in miami and used within 24 - 48 hours within that area, it'll go great!
now the hard part is actually finding a first hand dump supplier, and then said supplier actually give you fresh stuffz. that takes luck that no one can really help you with.