How can I charge a variable fee on an item?

[manousheh403]

I am using Square for Retaurants and I want to charge a delivery fee for our catering orders.  The fee that we charge is just a pass through from our third party that delivers them.  The amount depends on the order, and has a minimum as well, so ideally I can just have an item that when I click it would request the server to input the amount.  Is there any way to do this?  If not, how do you guys handle situations like this?

[manousheh403 · Accepted solution]

Ok I figured out if you just don't put a number in the price field it sets it to variable.