How do I modify a quote?
A quote remains open to change until the client or you confirm that the mission is "completed".
This is very important because it means that a quote is never etched in stone, so if you aren't sure of the exact length of the mission or if it is likely to be prolonged, you will be able to modify the quote during the mission.
And this also works if the client prepaid the mission. At the end of the mission we will either reimburse the difference or ask them to complete the payment.