I think it is similar - you buy the lease and it has a fixed term, you are responsible for renovations and there will also be yearly charges associated with the property. You are also able to sell on the lease if you want to, for either profit or loss depending on the housing market.
I've mentioned several times on these threads an example of a Windsor property owned by the Crown Estate but leased by a non-royal family is Fort Belvedere.
Built in the 1750s was home to various members of the royal family with the final royal to live there was Edward VIII until his abdication - he was given it as a 'gift' by his father but as it was still Crown owned it was never really his to own, he just occupied it as a grace and favour property which he paid to maintain.
He thought it would always be his to return to but (a bit like Harry and Frogmore) while he was living in France after the abdication, he was told he couldn't have it anymore as it was a perk of the job he'd given up.
Then it was empty for 15 years before being offered to be 'rented' privately on a long lease of 99 years.
That lease has been sold on several times to different people and the current occupants are a billionaire Canadian family who have live there since the 1980s.
The lease expires in 2053 so at that point the lease will need to be renewed or given up and bought by someone else.
en.wikipedia.org/wiki/Fort_Belvedere,_Surrey