There would be three ways to approach your problem. If they owned the house, there would be the wills index at the Registry of Deeds. It is now computerised, but not on line. The deed indexes for that period would show a purchase, sale or mortgage. They have been filmed and are in the Salt Lake Library and can go out to branches. Douglas was listed under Onchan parish. It is, however a possibility that they were tenants in the guest house, and the only records will be the Burgess Roll and voters list. As we have found on this board, names of guest houses have been changed over the years.
Some guest houses were owned by families such as the Gills. Also the Methodist Trust owned one or two, I think Mr. Trustrum had a few and so on...

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