BBL was not as I expected after a revision, what is the percentage of fat retained? Is it the same % as the first one? (Photos)

Ideal candidates are at a stable weight,  in good health , and have excess fat in some parts of the body and too little in other regions.  Gaining weight before the procedure is to no advantage and when you lose weight again the fat cells will shrink just like the donor site fat cells.  Typically, the transferred fat results in a significant increase in volume of the body site being treated.

We don't know how much fat was transferred in your case.  Sometimes when combination procedures are done, less fat can be transferred.  An example is if a full abdominoplasty is done, the front of the abdomen would not typically undergo a lot of liposuction.   In either case, having had significant weight loss can make it difficult to see a good volume enhancement for several reasons.  If you have a reasonable amount of fat available, a full liposuction and fat transfer can be performed.  I can't comment on the pricing, though many practices will discount a second procedure in your situation.  

It all depends on what was done. A significant amount of fat must be transferred for you to have a lasting result as 30-50% of the fat volume injected will be lost over the first 3-6 months after the surgery. Also, if a good majority of the volume injected was fluid (the PS did not separate the fluid off well), then your body just absorbs that fluid. Sometimes PS charge more to do a revision if the patient had the first procedure from someone else as it is more work to fix what someone else didn't do correctly. It is hard to give you advice without seeing before photos. It is up to each PS on how they handles "revisions". If he is going to charge you full price to do the procedure again, you may want to consider shopping around to make sure you get the best possible result.