Enter only one valuation method per line

What causes this issue?

You can use only one valuation method for each line.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Choose either
Material cost estimate (enter a quantity field as well)
Conditions (enter a costing sheet) or
User exit (enter an exit number) or
Transfer prices (enter a transfer price variant and a quantity or value
field

Error message extract from SAP system. Copyright SAP SE.