Can I prepare a report which shows the VAT element of unpaid invoices at the end of a month

Yes, you can customize the Open Invoices report to display the VAT amount for each invoice.

Here's how:

1. Go to Reports, then search for Open Invoices.
2. Click to open the report and filter by the desired reporting period.
3. Select Customize, then go to More Columns.
4. Click Transaction.
5. Under the Attributes section, select Show more.
6. Check the box next to Tax.
7. Once done, click Apply changes.
    

Also, you can memorize this report to automatically save your custom settings for future use.

Feel free to go back to this thread if you have more questions.