The data which I hold covers both current and past orders. This data is securely held to enable me to comply with statutory income tax requirements as a sole trader. The data is limited to contact information on invoices, receipts and current orders.
Where photography is concerned, images are archived in date order as a normal practice, and prints available at standard prices provided you can identify and tell me the date the images were taken. Images produced for media/newspapers etc. are supplied with appropriate caption information. Wedding images will not appear on blogs etc. without the express consent of the customer.
Otherwise I do not store customer details, and the only mailing list I operate is a general list of media outlets.