opencart-vqmod-tax-extension
vQmod Tax Extension for OpenCart
Price system in OpenCart adds tax to your products price, which means that if you already have prices with tax included in your list, you have to calculate price without tax and only then insert it into the system. Only then will OpenCart show your right price. I used vQmod(Virtual File Modification System) approach for this project. Sellers can now insert their product with total price with tax, so they avoid calculating the price without tax.