Changing parent plant

Probably the easiest way to do that is use CB Code Field. So first create your integer field for them to supply the number of licenses. Next in your code field multiply that by the discount per license. Now you just use that code field as the discount amount in your promotion. Example as follows.

Code:
The above would give a 10% discount if buying 10 or more licenses or a 5% discount if buying 3 or more licenses, but less than 10. Now you'd create the following automatically applied promotion.

Promotion Type: Applies to all purchases
The promotion is: R: A percentage R of the item price from a CB field
CB Field containing percentage: SELECT_CODE_FIELD_HERE

Now during registration and/or profile edit they fill out their licenses field with how many they need.

That is excellent, thank you but still the plan price is not increased by the increase of the number of licenses. It only discounts the plan price based on the promotion discount. Unless you mean something like calculating the price of the plan based on the discount rather than keeping the discount constant within the promotion, is that right? (I'm a bit confused) The orange color is what I expect to achieve somehow. Is that possible?

The above it is just an example to explain the structure, not the actual calculations.

To increase the price you just need to use a negative promotion. So instead of returning 10 you'd return -10. Example as follows.

Perfect Kyle,

Thank you!

One more question on this.

All work fine except that the price of the plan does not increase according to the int userfield. It only applies the discount.
In integrations->Family plans I have set as Limit the int userfield. To my understaning the number of shared users does not increase the price, so how can I make this do so?

EDIT: Sorry, it seems that you have already answered this above. So I suppose I will use the int userfield to increase the price of the plan. That means that there is no option to multiply the number of users by the plan price, correct?

EDIT 2: Unless there is another way, what I 've done so far and it seems to work is something like

All work fine except that the price of the plan does not increase according to the int userfield. It only applies the discount.
In integrations->Family plans I have set as Limit the int userfield. To my understaning the number of shared users does not increase the price, so how can I make this do so?

That parameter doesn't increase the price, but just limits how many users they can share with.

EDIT: Sorry, it seems that you have already answered this above. So I suppose I will use the int userfield to increase the price of the plan. That means that there is no option to multiply the number of users by the plan price, correct?

cb_licenses can't directly increase the price, no. You need to use a CB Code Field as provided above to calculate the price increase based off the value of cb_licenses. This can even just be simple multiplying math as shown below.



Note your above PHP was not correct. I've corrected it for you.