Which items?
The property has to be delivered to them in the same condition as it was when they contracted to purchase. So if there are any new holes, or things missing, they have a right to rectification.
If they're trying to argue that they're now not happy with the condition of the property, eg marks on the walls which were already there, or things which were broken already, then that's tough.
But from a practical perspective, they can still delay settlement and muck you around while you argue about it, so you're in an unenviable position (if you really want/need this to settle on time).
What kinds of things are they wanting you to fix?