Rather than cut and paste some legal boilerplate, I thought you would prefer a plain English breakdown of what data I collect, how it is used and how it is stored. In general, I respect that you have an absolute right to privacy concerning your information, and am also aware that there are potential security concerns with others finding out when you will not be at home whilst any events are on.
I'm only interested in gathering what I need to know about you and your event. Dates, locations, any special; requests and of course your contact information. This may be shared with performers and venues in order to get the right people to the right place, and to make sure that relevant information is available to anyone who needs to know. It is not, and never will be (subject to any legal/formal reasons) shared with anyone outside the contract, or for any other reason.
During initial enquires, I'll keep written details, emails and text messages to hand. I did try deleting this immediately after enquiries, but clients can come back to me after a significant gap - expecting not to have to start from scratch again.
Once a booking has agreed, I'll record all the significant information on a Google spreadsheet, stored in a G-suit account. This is so I can access it when out of the office - I have had to rearrange performers whilst stuck in the middle of a field in Norfolk, the service I offer will be potentially diminished withouth this facility.
All the relevant details for a performance are kept in a working file (stored in a safe when not in use) and sent to the band leader (usually me) or other person responsible on the night. This duplication has proven useful many times, modern tech is good, but paper and ink is more stable and robust.
After a booking, I destroy any documents with personal details, and delete the contact details held in the spreadsheet. Unfortunately, whilst this does mean that I comply with the legal requirements, It does make it harder to search back through to find past events - for example, 'you did our wedding, can you do a naming ceremony/anniversary? Please bear with me if this causes hassles in the future.
Please do let me know if you have any suggestions or specific requests regarding your data.