I have had several instances where we have created the estimate and/or contract and requested the signature only to need to change something in the estimate or contract after meeting with the customer (such as editing the shingle color or updating the warranty years and price if they choose to upgrade) and have had to create a whole new document/estimate because I am unable to edit the one that already has requested the signature. If they haven't signed the document yet then I should be able to edit it and resend it rather than make a several versions of them and then not be able to delete the older ones.