24 Years old, 180 lbs. Getting BBL with fat transfer - how much weight do i need to lose?

I want to lose weight but not too much because I still want a huge butt and a smaller waist. I have seen lots of pics of womens before and after and I don't see much of a difference. How much fat should I request to be transferred? 800cc 1100 cc? I want the most to be injected to it is noticeable. How much weight do I need to lose? Where else on my body do I need to try and loose weight? Or should I gain more weight to make sure my butt is huge because 30% of the fat will go away over time?