No one is going to be able to give you an answer to this that will be helpful or applicable to your own situation. There isn’t a set spend for any offer, let alone per color. There are far too many factors, including many intangible factors, to make any one else’s experience relevant to your own. Where you shop (both country and actual store), how much you spend, what you spent it on, what other clients of your SA/store have purchased, what your store has ordered, which bags they’ve already received, how long you’ve been shopping, how long everyone else has been shopping, how many other clients at your store want a white size 25, how many other clients have already received a white size 25, how long it’s been since all requests for a white size 25 were made, which SA is on duty the next time a white size 25 is delivered, how long it’s been since your SA has been granted a coveted quota bag to sell, if your SA thinks of you above all her other clients the next time she gets a white size 25, how many bags each of the other clients who want a white size 25 have on each of their wishlists and what priority this bag would be on their list, etc etc etc.
The only things in your control which will help you are to: shop often, shop generously, and be a pleasure to deal with while being patient. Everything else is outside of your control.
