If a user tries to open a Workbook that is already open, then they normally get a message saying that the File is locked by a certain user and would you like to open the file in Read only mode. However, you can open a workbook in shared mode by following these steps. First open the file that you want to share, then once the workbook is open, go to the Tools menu and choose Share Workbook from the drop down menu. The Share Workbook dialog box will now appear. To enable sharing, you simply click once on the Allow Sharing check box, so that it has a tick. Once you do this other people will now be able to use your Excel workbook whilst you are working on it.
Another source of information will be the bills and receipts that you have received over the past quarter. If you have not kept such documents and records before, then now is a good time to start. The good organisation of your important financial documents, and orderly filing of bills and receipts, will stand you in good stead for controlling the family budget when it is set.