As part of the process, we'll compare the original check-in inventory, with the check out inventory and look for differences. We are looking to make sure they are the same, but it's those differences that are crucial.
We'll then need to see if the changes have been caused by general wear and tear, or misuse or neglect by the tenants. For example, if there is a small mark on the wall in the hallway, we may take the view that this is wear and tear, if the tenancy ran for a number of years with multiple occupants. However, if there is a hole in the wall, we may have the opinion that it has been caused by misuse or neglect.
Your tenancy agreement will stipulate how your deposit may be used if it's deemed needed.