To track the progress of a sale, you can use the "Sale Progression" side-menu against the sales property.
Click "Add" to record new events, and add notes as required.
Custom sales progression checklist
If you want a custom checklist for managing the progress of a sale, you can set-up a new "Sale Progression" checklist under the top-level "Templates" tab. You can then use this to tick off steps in the process as and when they happen.
For more details on how to set-up checklist templates, please refer to this article.
Sales In Progress alert
To keep track of your sales currently going through, you can use the "Sales In Progress" alert. This shows any properties where a buyer has been found but the sale hasn't completed yet (or completed within the last 7 days). Click the green "+" icon to expand to see details of the sale progression.