If you don’t know what GP and Retail Value refers to then there are bigger issues. I really hope its just translation issue.
GP = Gross Profit, Profit after direct costs (what materials go into it directly)
Retail/Sale Price (what customer pays) - Cost of Goods (ingredients put into dish)
For GP% this is also then divided by the Retail price again to give GP%
Our GP% target is 69% average on total dry/food sales - obviously different dishes return different % and a sandwich or simple dish might hit 80% a steak might come in at 50% but average target overall is 69% for us.
Retail = What you sell a product for to the end user/customer i.e. not trade etc.
Different countries include tax, others do not but main thing in general is whichever your country does you generally would need to apply same principle to cost price in calculations - i.e. if calculating GP/GP% on a tax inclusive price you would need to remove tax given that there is generally little VAT on raw food purchases.
In short you generally calculate using exc tax on both sides.
Kendash has inventory side covered.
My setup was for simple retail product record of spillage/damaged etc.
Either way my previous questions still stand.
Purchase price changes, what happens when you buy 1 bottle of ketchup (you ingredient of choice) for say £5 last week and use half then buy another bottle at £7.50 this week then throw away the half bottle because its gone bad (not that ketchup would like that) I know in this example its obvious its the half bottle that cost £2.50 from last week but you latest price was £7.50 for a bottle… You need to explain what it is you want o do CLEARLY and then we can make suggestions…