We are going to be offering a new type of service with some of our products. Two of the services will be generating an "amount off of invoice" which is creating a problem, as they are amounts that are negative.

When we try to enter a new item in our inventory, that has a negative amount as the base price, we get a warning that says "Value must be between 0.00 and 9999999.00

Is there a way to enter a new product code with a negative amount?

Thank you.

No

If you allow credits on Invoices in the OE Company Profile, you can ship a negative quantity of an item.

To see how this would work, set up a non-stock item for the discount with a value of $1.
To give a $20 discount, enter -20 shipped and you will see the value of -$20.

Of course, you can also use the discount on the totals page to enter a discount amount.

Does that give you what you need?