I would like the ability to have invoices automatically locked after sending them, so that they cannot be edited.
I frequently add multiple items of work to a single invoice over a period of several weeks, then send the invoice and open a new one - however, occasionally I forget that I've already sent it and continue adding items to an invoice that the client has already received, which is obviously highly undesirable. If the invoice were automatically locked, it would prevent me from making this error.
"Lock invoices after sending"
