Restore to a good state of repair (8)
I believe the answer is:
renovate
'restore to a good state of repair' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for renovate that I've seen before include "Modernise" , "Restore to a good state of repair" , "Restore to good condition" , "Renew" , "Make as new" .)