This should give you a start.
The 1930 Census for Vallejo, Solano County, CA, renting 803 Marin St.
Martin X(Transcribed as "B", but looks like it could have been a "V," then overwritten.Enumerators also are wrong in transcribing data, heard a "B" when the initial was "B").age 58, born in Illinois to both parents born in New York, Chief Clerk/Navy Yard.Identified as being married, age at first marriage: 40.
Brook Edmonston, age 65, Roomer, born in Illinois to father born in North Carolina, mother in Missouri, Clerk/Navy Yard. Widower.
--Note: This Martin would have been born about 1871/1872.
This person was living at the address you provided.
This person was born in Illinois...see next:
The California Death Index:
Martin V. Davis, died 12 August 1955 in Sacramento, CA, born 6 Jan 1872 in Illinois.
In burials, I find this interesting to connect both:
---Martin V. Davis, buried in Sacramento, born Jan 6, 1872, died August 12, 1955
Buried in Section E, Lot 27, Gr 1.
---Adella Davis, born July 4, 1866, died May 28, 1958
Plot, Sec. E, lot 27, Gr 1
NOTE:This Martin V and Adella Davis are ofabout the same age group, and buried in the same area.The Odd Fellows might have more information on them:
2720 Riverside Blvd, Sacramento, CA, 95818
NOW that we have a good idea who this person might be, I looked in posted family trees:
There were seven, including:
owned by a jfccrow.Identifies Martin Davis, born 6 January 1872 in La Salle, Illinois, died 12 Aug 1955 in Sacramento, CA.He married Della M. White, born 1878, on 19 July 1911.No source data for wife or marrage date.Martin was son of George Davis, 1831, New York, to 1 mar 1911 in Long Beach, LA County, CA.His mother was Catherine C. Foote.They had eight children (including Martin).There were pictures of parents and siblings.If you do not have access directly to Ancestry.com, you can try your local library.Most have access using their computer system, using your library card.
It strongly appears that Martin and Adella are buried together in Sacramento, but no indication why they were not shown as together in the US Census.Perhaps he was living at work, while she was at home during the census enumeration and they rejoined together later.The family trees do have a good connection to this person; BUT you can not take someone else's research data to be correct without DIRECT source information.The info on Martin and his family appears to be of good value; but there is little information on his connection to Adella/Della.