Mate being miserly -- about right, with average rise of lease (8,7)
I believe the answer is:
sparring partner
'mate' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'miserly about right with average rise of lease' is the wordplay.
'miserly about right' becomes 'sparring' (I can't explain this - if you can you should give a lot more credence to this answer).
'with' is a charade indicator (letters next to each other).
'average' becomes 'par' (I've seen this before).
'rise of' says the letters should be written backwards.
'lease' becomes 'rent' ('rent' can be a synonym of 'lease').
'rent' reversed gives 'tner'.
'sparring'+'par'+'tner'='SPARRING PARTNER'
'being' is the link.
Can you help me to learn more?
(Other definitions for sparring partner that I've seen before include "disputatious associate" , "hits rehearsed with me?" , "What a boxer needs" , "Ring mate" , "jabber" .)