I need an extension for the admin of opencart. There are a few similar ones out there to buy that are very cheap but I need something exactly to my requirements. I need to have a 'cost price' for each product. I also then need a 'sale price' box for each product. Near the 'sale price' I need a drop down that will say 'select price markup'. In the admin I want to be able to create my own 'price markups' (these will be calculations such as COST X 1.6 + £20). Each price markup I create needs to allow me to select the name. I want to be able to select the defaut price markup in the admin so that all products are set to the default markup. I also want it to allow me to select from this drop down to use a fixed price (no calculations) so that I can still enter the sale price manually in the box as normal without using any markup prices. When I create a markup I want two parts to the markup, a MULTIPLY box (so X 1.6 as an example entry) and then a ADD box (so + £20 as an example entry). The sale price after selecting the markup needs to simply let me save that and it will then show the new calculated sale price on the front end. The sale price also needs a feature that allows me to set the price to round up OR down to the nearest £1, £5, £10. So there should be a field under sale price where a drop down says 'round up', 'round down' and 'do nothing' - and then another drop down that lets me select 1, 5 or 10 as the round up/down figure. This way if the price calculated is £32 and I select 'round up' and '£5' then it will show as £35. I also need it to show the calculated price when I select anything on the drop downs so I can see what the end 'sale price' will be. The cost price and sale price need to be visible on the table when you view all products so that I can see them clearly. Needs to be compatible with ALL my admin extensions (eg. I have an extension to allow me to edit prices from the admin products list view without having to click on the product - this will be simple to do).