Outside posh hotel, salespeople knocked back wine and soda (8)
I believe the answer is:
spritzer
'wine and soda' is the definition.
(I've seen this before)
'outside posh hotel salespeople knocked back' is the wordplay.
'outside' indicates putting letters inside.
'posh hotel' becomes 'ritz' (I've seen this before).
'salespeople' becomes 'reps' (I've seen this in another clue).
'knocked back' says the letters should be written backwards.
'reps' in reverse letter order is 'sper'.
'ritz' inserted inside 'sper' is 'SPRITZER'.
(Other definitions for spritzer that I've seen before include "Wine mixed with sparkling water" , "Wine and soda cocktail" , "Wine and soda mixture" , "Ritz reps has drink of white wine and soda water" , "Drink made of wine and sparkling water" .)