You can look up addresses in Scotland in the One Scotland Gazetteer.
It is good they provide a search facility where one can lookup the Unique Property Reference Number (UPRN) for a premise, as well as check where located.
I could not find some flats at first if don’t match way record held. The search is not as good as could be as does not seem to search all fields in the record, and the result does not display all the fields I assume recorded from BS7666 spec, I am particularity interest in the locality, as opposed to just the town. But at least it is some access to these records.