I work in school admin and there are new DP rules coming in. I have researched this and had some schools interested in employing me on a freelance basis to act as their DPO. I don't know how much to charge. There'd be an initial set up (probably 20+ hours) and then on-going monitoring. This is the state sector so budgets are tight! Any suggestions welcome.
Most LAs are offering this service. It seems very expensive and frankly out of the reach of most small schools, so many are clubbing together on a consortium basis. Maybe try finding out what your LA is charging.
Our LA quoted something close to £8000 initially, but has had to reduce considerably, simply because schools couldn't afford to pay it. In the end it's costing us £700 per school as part of a consortium of secondary schools.