Replace the Sovereign Grant (£86.3m in 2021-22) with a system of voluntary contributions where members of the public can decide whether to contribute to the official expenditure of the Royal Family.
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The Royal family and its duties are respected by many; others are ambivalent at best. There is not unanimous support.
Support could be gauged by determining how many are prepared to pay for a service, and what value they place on it.
A fully-costed and transparent target budget could be set 12 months in advance, and a 'crowdfunding' appeal launched to achieve that target.
Tracking against target would facilitate adjustment to resources in the case of shortfall or oversubscription.