How to add a fixed charge?

How can I add a fixed charge that is calculated based on quantity (once time)?
In addition to the standard price that changes with the amount, I need to be added a fixed cost.
for example: "setup charge". better if for each product tab

I'm not sure I understand what you want. Could you explain a bit more what you want and why ?

there are item which should be added only once, independently of the quantity. Example: setup costs or startup costs. As can I add these fixed costs?

Why not use shipping methods to add these fixed costs ?

But I have already set the shippijng methods (for delivery)

Then that would require to handle an extra product in the cart via custom code in the views of the checkout. It woudl require to have a developer work on that for you.

I try to explain with a practical example:

Product A Unit cost: 30,00
Q.ty 100 = 3000
Print setup (colour) = 25,00

Tot. 3000 + 25 = 3025 euro

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Product A Unit cost: 30,00
Q.ty 100 = 3000
Print setup (only black) = 15,00

Tot. 3000 + 15 = 3015 euro

As you see, I have two type of "print setup" and I don't set it in shipping cost, because changes depending on the selected setup but at the same time the cost is calculated once only and doesn't change based on the amount

How can I add a fixed cost as Print setup B/W and Print setup Colour??

Maybe you could do that with an option product:
www.hikashop.com/en/support/documentatio...ct-form.html#options
That would have to be tested but here is how I would see it:
You add an option product for each "main" products so that the users can select the print setup for each product they want to buy. In the option product, you set a maximum quantity per order and normally the main product will have its quantity added normally to the cart while the option should have only one item added when you add the item to the cart.

Otherwise, if that doesn't work, it would still possible to do it with a custom field, of the table "item" if it's per product, or of the table "order" if it's for the whole cart, and then create a small plugin to add that fee with some code.
If you're a coder it shouldn't be too complex once you know the trigger.

I have the same requirement. I don't understand why this isn't part of the product as most other cart options have this.

Ok, that works. I added a product with a maximum of 1 per order