… runs away from case of deplorable valets possibly trashing vehicle (7)
I believe the answer is:
deserts
'runs away' is the definition.
(I've seen this in another clue)
'deplorable valets possibly trashing vehicle' is the wordplay.
'deplorable' becomes 'de' (I can't justify this - if you can you should believe this answer much more).
'valets possibly' becomes 'servants' (valet is a type of servant).
'trashing' is a deletion indicator.
'vehicle' becomes 'van' (van is a kind of vehicle).
'servants' with 'van' taken away is 'serts'.
'de'+'serts'='DESERTS'
'from case of' acts as a link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
(Other definitions for deserts that I've seen before include "Walks out on" , "Arid areas" , "Sahara and Gobi" , "Leaves" , "Wastes" .)