How to Use Form Calculations to Calculate Billing for Client?

is there a way to calculate someone’s purchase such as if they pick the amount to be 1-3 they will pay $10 per item on top of the charge of the item. Then if they pick an amount of 4-10 then they will pay $5 more for the whole set. Then if they order an amount of 11-20 5% discount, 21-50 10% discount, and 51+ 15% discount.

Yes, this is possible by passing a calculation on to a payment field.  You can then use conditional logic to calculate values for fields on the form.

Do you already have a form on which you would like to apply these formulas? If so, please provide the link URL here and we could take a look and configure it to work the way you require.

https://www.jotform.com/build/90277102466152

 

Here is the link please let me know if there is anything else I can do. I'm currently working on the configuration but any help would be greatly appreciated. 

I'm not sure what is the base price of the products?

If you could please clarify, this is the base price: 

And that base price should be changed according to selection here:

So if you choose the first option, the price should be Print size * Number of prints + 10$/panel?