Dr. Thomas Green writes: The brick building in your photograph was built as a bank, or so I was told as a kid. It was closed by the time I was around (born 1960) and was later used as a general storage building/warehouse. Montrose was a thriving little town during the first half of the 1900’s, with several stores, bank, physician office, railroad depot etc. Not much left there now, sadly.
Vanishing Georgia: Photographs by Brian Brown 
I was born in 1955 and have always lived in Montrose. I always heard this building was a jail.
Hi Brian. My name is Thomas Green. I currently live in Fitzgerald (since 1992) but was born and raised in Montrose. The brick building in your photograph was built as a bank, or so I was told as a kid. It was closed by the time I was around (born 1960) and was later used as a general storage building/warehouse. Montrose was a thriving little town during the first half of the 1900’s, with several stores, bank, physician office, railroad depot etc. Not much left there now, sadly. The row of white storefronts in your next photo did house a small general store during my childhood, run by a Mr. Y. H. Thompson, complete with wood-burning stove. The two-story building was the Masonic Hall, also now defunct. The small block structure was/is (?) the voting building. Only time it was opened all year, as far as I recall. Mr. Payne had a auto repair shop in one of the other buildings (previously store, I think). Anyway, thought you might want to know. Thanks for your excellent site, and for your effort to record our vanishing way of life.
Possibly a auto repair garage or part of a early auto dealership and supporting garage.