# Calculating sales tax backwards from final price

I'm in the EU and my pricelist includes 19% VAT (sales tax). (This is required by local law. We cannot provide retail pricing without VAT included. So, all prices are rounded after VAT inclusion.) The problem: If I enter each item with its price divided by 1.19 (to get the pre-VAT price), it almost works but the problem is the final total (due to rounding errors) is not accurate. For example, Product Price is EUR 125 (pre-VAT that is approximately 105.042016..., not a nice round number) Shipping cost EUR 10 (pre-VAT that is 8.40336134...) When VAT is added for the invoice, these end up showing a total of 134.99 instead of the correct 135, because of intermediate rounding errors. What I want to do instead: I would like the calculation to go backwards. That is, for the total, start from the 135 (based on the declared prices of 125 and 10 for the example given), allocate VAT [by doing 135*19/119, or price*VAT_RATE/(100+VAT_RATE)] and then do the same for each individual invoice line [calculating pre-VAT price for each item line by doing price*100/(100+VAT_RATE)]. In all cases results should be rounded to two decimal digits. That way, the totals will be correct both for each line(specially, in case of multiple units per item) and for the grand total. Is this possible? (I can do all the calculations and roundings by hand in advance but it's a waste of time.)Also, is there a way to tell Quicken to round on two (or four) decimal digits for each invoice line seperately? Although, this will work a little better it still isn't as accurate as the above because when dealing with multiple units, the per unit price will be off.