LetMC will apply notes relating to people or properties when you carry out an action, for example if you check out keys or add a maintenance job. You can also add additional notes to people or properties on the system.
You can carry this out by typing add note and then entering the person that you'd like to link the note to.
Alternatively you can click into the person or property profile and click notes on the left hand ladder:
Here you can enter the notes in the free text box and click add to complete.