Something like a valve you expect to get at a shop (5)
I believe the answer is:
value
'shop' is the definition.
The definition and answer can be both to do with ownership as well as being verbs in their base form.
Maybe there's an association between them I don't understand?
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for value that I've seen before include "Hold dear, regard highly" , "Precise meaning" , "Cost" , "Worth; prize" , "Hold in high regard" .)