Read this: Albert assumed the regnal name "George VI" to emphasise continuity with his father and restore confidence in the monarchy. The beginning of George VI's reign was taken up by questions surrounding his predecessor and brother, whose titles, style and position were uncertain. He had been introduced as "His Royal Highness Prince Edward" for the abdication broadcast, but George VI felt that by abdicating and renouncing the succession Edward had lost the right to bear royal titles, including "Royal Highness". In settling the issue, George's first act as king was to confer upon his brother the title and style "His Royal Highness The Duke of Windsor", but the Letters Patent creating the dukedom prevented any wife or children from bearing royal styles. George VI was also forced to buy from Edward the royal residences of Balmoral Castle and Sandringham House, as these were private properties and did not pass to George VI automatically. Three days after his accession, on his 41st birthday, he invested his wife, the new queen consort, with the Order of the Garter.

What royal residence did George VI own?
What is the answer? (If it cannot be answered, return "unanswerable")
unanswerable