Appraisal for "Capodimonte Special Order Chandelier"

Hello, I purchased this Capodimonte Chandelier 10 years ago from a million dollar home in Florida. I saw the an identical one in EBAY for $10,000 9 years ago. When I purchased the chandelier the seller told me it was from the 1920’s. That she had inherited it from an ancestor. To me, it looks vintage but not sure of the age. Can someone tell me what it is worth and the approximate age? Alsso I would like to get a Certificate of Authenticity can some one tell me how I can obtain one? Thanks Manny