Grandma was born at her parents’ home on what’s now the highway west of town in 1924. That’s where all her siblings were born.
Grandma’s birth certificate indicates she was born in Prairie Township, Hancock County, Illinois, in 1924. That is as precise as it gets. There is no address listed. My transcription should only indicate what is given on the certificate. If family tradition indicates the place of birth more precisely, that should be put in the notes–along with the individual who provided the information or my reason for believing it. Always include a source.
Earlier records may not be as precise. Some marriage records only indicate the county of birth–so that’s what I should list as the location of the event. For some individuals my knowledge of the place may only ever be as specific as the county–and even then that may be speculation.
The same thing goes with dates of birth. For many of my Virginia ancestors before the early 19th century, my “dates of birth” are only as specific as the year and the location is as specific as the county. Even those locations are based upon where the mother was presumed to have been living at the time of the birth.