William sandall seems to be in billericay in the 1939 register, you can search the free index on find my past using address search, Cheltenham drive is easily found by entering Essex as the county, you have a choice of two, choose the one in Southend

As you know the house number you should find a preview.
To open the record costs, and lookups for you are not allowed on rootschat.
A better option, since you live there would be to ask the local library where you can look up the electoral rolls for 1938, that might tell you who was living there then,
Mike
M