I presume you have already emailed the Manager of the Andel Hotel to see if they have any old photographs? If no reply from a letter or email, try a friendly 'phone call. Often people mean to reply, but are busy and don't.
Newspapers in the past often kept a Card Index of people, places and buildings, so the King's Lynn and possibly County newspapers are worth a try?
Try the Chair of Local Historical Societies? Two Local history Societies I know of, won't donate anymore of their Archives or photos, because County Archives had still not listed items years later.
Also the 1995 Selling Agents Landles, likely the same Landles of King's Lynn, established 160 years
https://www.landles.co.uk/ may have sold the building before and just might have an Archive of Photos (many don't keep Particulars), but worth a try?
I once got a 1933 photograph of our village Pub by tracing the families of Licensees, from a Granddaughter of one.
1869, 27th February
Captain Willis, Oakwood House, Tottenhill, Lynn Advertiser, Norfolk
1881 Oakwood House, Lynn Road, Tottenhill, Downham, Norfolk
Major General,
Charles Parker Catty, Head, Mar, 55, Major General Retired full pay, born Florence, Italy, British Subject.
Eleanor Georgina Catty, Wife, Mar, 26, born Hintlesham, Suffolk
George Royal, 18, Footman, born Northwold, Norfolk
Sarah Ann Walker, 25, Cook, born Tilney St John's, Norfolk
Added: When, Eleanora Georgina Deane married Catty, a newspaper notice mentions the ... Bishop of Bangor, Cousin of the Bride ... also, the youngest Daughter of the late Rev. W. H. Deane, Rector of Hintlesham.
1881 Surname had been transcribed Colby, but reads Cally. Ancestry and f m p also Colby and Anc., suggest Catty.
The 1901 Census at Portsmouth, Daughter, Pearl A. M. Catty, 19, so looks like she was born 1882, Mother Maiden Surname: Deane, but Births Index says Pearl was registered District Cosford, Pearl Alexina Macdonald Catty.
1921, 7th October relating to a car accident
30th September, Mr F. R. Whitbread of "Oakwood", Tottenhill, met with a ...
Whitbread at Oakwood in 1914 & 1917 newspapers.
Probably, Frederick Robert Whitbread, because in the 1911 Census, a Frederick Robert Whitbread gives his address as Tottenhill.
Added: the 1911 Summary Census Books confirm his residence as "Oakwood House" Private House, Mr F. R. Whitbread.
1937 Frederick James Palmer, 75 years, Abode, The Oakwood, Tottenhill.
1937 Betsy Maria Palmer, 74 years, Abode, The Oakwood, Tottenhill.
Burial
1952 Dorothy Susannah Boon Palmer, 51 years, Abode Oakwood House, died at Evelyn Nursing Home, Cambridge.
Probate 1952 to Frederick George Boon Palmer.
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Regarding Setchy, Setchey, the Norfolk place appears to have also been called Setch in documents (a few in the return are Setch surnames unfortunately) ...
https://discovery.nationalarchives.gov.uk/results/r?_aq=Setch%20Norfolk&_dss=range&_ro=any&_st=advPoster Dyingout is also correct, still Setchey on modern day road maps.
Regarding exact searches, the place to the North seemingly has spelling variations.
Mark