Apparently someone left £50m as a bequest to the RF, for the purpose of building a new yacht. I think the £200m estimate is a recycling of the RN's plans for a replacement at the time Britannia was sold off, which would have cost £110m at the time (thus the estimate of £200m today). I wonder what support it would get from the public if they tried financing it via public subscription, with "grants" from various Govt. departments (Industry, Education, Trade, Foreign Office) for the expected benefits for their respective sectors - it would be more politically neutral than "us Tories is building Madge a new party yacht".
For a light-hearted look at what it might look like
https://www.boatinternational.com/yacht ... ike--42967
and if you want to know why Britannia was designed the way she was, this is an interesting looks at the requirements (like a Royal Yacht needs three masts, to fly the Royal Standard at the Main, the Flag of the Lord High Admiral at the Fore, and the Union Flag at the Mizzen).
More effort went into the Hospital Ship part of the design than the "Royal" elements, apparently
https://www.royalyachtbritannia.co.uk/m ... -paper.pdf
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