Determining the Correct Top-Up Amount for a Project Budget with VAT Considerations

[goodfriends1]

I want to place an order for an $80 project. I would like to know how much I need to top-up in my budget to cover this amount, including the VAT. How much is the VAT? Is it 19%? If so, do I need to deposit an additional $15.2 based on the $80? Currently, I have only topped up an additional 10%, but if 19% is required, I want to know if I will be notified later about the shortfall and how I can make the additional payment. As a priority, I also need to know how much I need to top-up for a $100 project.