This is Frank Kristof’s World War 1 Draft Registration Card. It is the only bit of information I have found so far that confirms the presence of an ‘F Kristof’ at 1700 East 31st Street, Lorain OH. I’m not sure he’s the building’s namesake, though. It doesn’t make sense that a single, 25-year-old ‘lake seaman’ would have a brick and mortar shop that’s he’s not around to tend. [see update below!]
EDITED TO ADD, courtesy of Reader Rick:
“The Frank Kristof that you found is almost certainly the son of the building’s owner. The 1920 census records list a Frank Kristof, age 59, as living at that address, with his wife Druhala and 4 roomers. At that time Frank was working at the steel plant and his wife’s occupation was listed as grocer, own grocery store. So the building apparently housed the Kristof family, 4 roomers, and a grocery store.
In the 1930 census, Frank (age 69) had apparently retired from the steel plant because his occupation was now listed as merchant, grocery. He was still living in the building with his wife and several roomers.”