I’m a small business owner trying to figure out how to properly use a VAT calculator for my invoices. I'm a bit confused about how to apply the VAT rate to different types of products and services of how to calculate vat in south africa. Should I always add the VAT to the final price, or is it sometimes included in the price already? 

Also, are there specific VAT rates for different product categories? Any tips or recommended calculators would be greatly appreciated! 

Thanks in advance for your help.