Having the salesman walk up to is smart (6)
I believe the answer is:
dapper
'is smart' is the definition.
(I've seen this before)
'having the salesman walk up' is the wordplay.
'having the salesman' becomes 'rep' (I can't justify this - if you can you should believe this answer much more).
'walk' becomes 'pad' (padding is a kind of walking).
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'rep'+'pad'='reppad'
'reppad' reversed gives 'DAPPER'.
'to' is the link.
Can you help me to learn more?
(Other definitions for dapper that I've seen before include "Rakish" , "Neat, spruce" , "Debonair" , "Neat and stylishly dressed" , "Smartly-dressed" .)