Purchase ordered: love what’s included! (7)
I believe the answer is:
toehold
'purchase' is the definition.
(thesaurus)
'ordered love what's included' is the wordplay.
'ordered' becomes 'told' ('tell' can be a synonym of 'order').
'love' becomes 'o' (love means zero in tennis).
'what' becomes 'eh' (I've seen this in other clues).
'included' means one lot of letters goes inside another.
'o'+'eh'='oeh'
'told' going around 'oeh' is 'TOEHOLD'.
(Other definitions for toehold that I've seen before include "Minor position from which further progress may be made" , "Position of initial advantage from which further substantial progress might be made" , "Advantageous position" , "Small established position" , "Precarious footing?" .)