Aircraft owners invest millions  into their aircraft and part of that investment is in the interior. All interiors are issued a burn certificate when manufactured or modified. Doing any maintenance on this interior including, repairing damaged areas, or re-dying can very well void an existing burn certificate. An item that many aircraft brokers review very closely is any interior work that may have been performed over the life of an aircraft that is being purchased or sold. If burn certificates are not in place or void because of unauthorized service being performed this can devalue greatly an aircraft. Many times the only solution is to completely refurbish an interior to bring it again back into compliance.