If you are locked into a multi-year contract, you could try one of several options at the AGM.
1) a mild option would be to have a Discussion item on the agenda ‘to discuss concerns to do with the quality of maintenance and cleaning, documentation of approvals and giving residents notice of works.’ That would give all a chance to air grievances and amounts to giving the committee and the manager notice that they need to do better.
2) a heavier duty option would be a motion for a resolution at the AGM requiring the committee to provide a written report to the next AGM documenting improvements to the quality of maintenance and cleaning, documentation of approvals and giving residents notice of works.
3) I notice you say you have had this strata manager for three years. In the ACT, perhaps similar elsewhere, 3 years is the maximum for a service contract. So, here, the manager’s contract would be up for renewal and there would have to be a AGM agenda item with a motion to renew the contract for a further three years. You could put an alternative motion, to go ahead of this one in the agenda, to only renew the contract for one year. If that motion passes, the next motion for three year renewal would lapse. You would explain the purpose of your motion is to provide an opportunity for the incoming committee to review the performance of the managing agent and then recommend either renewal or replacement at the next AGM.