display price with tax and discount

Hi,

Having the tax included on the products listing in the backend is possible if you activate the "show taxed prices" setting of the HikaShop configuration.
Having the discounts taken into account is not easily possible. It would require some non trivial custom code to load the discounts, process them, etc.
And there is no option to take into account the taxes and discounts when exporting products in mass actions.
If you use the Google products plugin, the XML it will generate for the products will contain the price for each product with the taxes and discounts taken into account. That's the closer to it that you'll get without any custom code.