For some of my products (telecom per-minute rates or USA IRS mileage reimbursement rates) I need to have the product price field extended to 3 or even up to 6 decimal digits. But I also need to round invoices, sales orders, and receipts to 2 digits. But changing the rounding and decimal precision for the Account module (Settings / Configuration / Accounting / Decimal precision on journal entries) (or via the currency config) changes both the product price shown in invoices, expense reports, etc., and the total amount of the invoice. Is there a way to temporarily or permanently make the whole invoice rounded to just 2 decimal digits? To most customers, having an invoice amount of $23.23458 would be confusing when they go to write their check to me. I would like the ability to have all lines in the invoice extended to whatever decimal precision the product is set up for, but still round the total for the invoice to amounts the currency can actually be paid in. How would I do that?
In the User Access rights, enable "Technical Features". Go to Settings > Technical > Database Structure > Decimal Accuracy > Product Price
A more detailed answer can be found here : https://accounts.openerp.com/forum/Help-1/question/1299
Don't forget to restart the server for the change to take effect.