How much fat can be taken out and put into my butt with a BBL? Can my Dr. put in more fat if I was once very over weight?

Is there was a limit as to how much fat a surgeon can take out at a time? Now I have lost 100lbs over the last 2 years and my Dr. was saying he will "try" to put as much fat as he takes out into my butt (since I am wanting it to be BIG). He said that as much as it will hold? What does that mean? So since my skin has already been stretched (and I use to have a rather large butt before) do you think he can put a lot in? I also want fat transf. on my actual sides/hip area, is that possible?