How complex could be change tax module to calculate tax amount from profit not from net ammount

In Spain (i dont known if in other countries is calculated equal) the tax on second hand produts is calculated on profit in sell, not from net amount at buy. How complex could be adapt account app to support this?

Sorry to inform that ERPNext cannot be configured to address this scenario. Can you please create a Github Issue for this feature suggestion?

As a work-around, you can enter Item’s selling rate in the other Custom field. Ensure that Amount field has profitable amount. On an item, tax is calculated based on the value in the Amount field. Currently, amount is calculated based on Qty X Rate.

Sorry for the delay in the response, I was traveling: \

The key here is that this change affects many things, for example the guarantee is changed to one year not two (exception to European law). There are two net bases in the sale, one with tax and another exempt, and goes disaggregated when taxes are presented. The products have a period where they can not be sold due to police control. The product is unique is always stock one unit and once sold never again exists (it is like creating continuous variants, discard them on sell and all costs and parameters/information are on variant not product). And there are a lot of behaviours like those …

That’s why we asked about information about change the financial part, that is the most complex and important, to see if it was relatively simple to modify. Here we have a development department, there would be no problem to adapt erpnext (and release the code to the community). But if it is more complex and will take more time to do it by hand and breaks erpnext default workflow, it has no sense.

We are in love with the erpnext interface and the doctype functionality, but we are a special type of business and we believe that erpnext does not fit perfectly with our workflow. We see the need for many changes and we are seeing that it is not easy to extend the erpnext core as create new apps with frappe.