Property to develop? Not at first (6)
I believe the answer is:
estate
'property' is the definition.
(estate is a kind of property)
'develop? not at first' is the wordplay.
'develop?' becomes 'gestate' (I've seen this before).
'not at first' means to remove the first letter.
'gestate' with its initial letter taken off is 'ESTATE'.
'to' acts as a link.
(Other definitions for estate that I've seen before include "Scheme of new housing" , "Total possessions" , "Follow on" , "Vehicle" , "Family land" .)