A good candidate has enough fat available for transfer in the procedure. The amount of fat that can be transferred in a BBL depends on how much fat the patient has to harvest and the amount of space there is to move the fat into. It is recommended for the patient to have a BMI of 30 or less. If...
Generally, an elevated cholesterol level slightly put you at a higher risk for any surgical procedure including BBL and lipo. However, cholesterol level is a single value, there are other aspects of your health that collectively can tell how much is your risk for the surgery.
You should be able to undergo surgery with general anesthesia even if you have mild sleep apnea. But I would suggest a medical clearance from your physician.