How to prevent Invoice gets forgotten?

[Nico]

Hi,

we have sometimes Issues/Tickets where we need to invoice the customer. 

Now i have an idea, of how to get this to to be prevent forget the invoice.

1 Filed "Sum" > enter 350 EUR for example

1 Checkbox "Invoiced"

If i close a ticket and in "sum" is a value entered, then closing should only work if the checkbox is checked. 

Maybe some one has another idea?

[Aron Gombas _Midori_]

I am not sure if it is better, but you could use a specific status for that, and your workflow could look something like this:

Open -> In progress -> Resolved -> Invoiced -> Done

It saves the need for the field, and maybe transitioning to "Invoiced" has a very explicit meaning. It also has a timestamp and the user who made the transitioned.