Old hotel employee, one finding foreign buyers (8)
I believe the answer is:
exporter
'one finding foreign buyers' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'old hotel employee' is the wordplay.
'old' becomes 'ex' (prefix meaning former or onetime).
'hotel employee' becomes 'porter' (type of hotel employee).
'ex'+'porter'='EXPORTER'
Can you help me to learn more?
(Other definitions for exporter that I've seen before include "One sending goods abroad" , "one sells abroad" , "One selling abroad" , "trading abroad" , "Overseas trader" .)