My requirement is that, a new accounting document has to be created based on a condition in the tcode FBZ1. The user will decide whether a particular tax has to be collected or not based on the incoming invoice. So we are planning to have a check box of the initial screen FBZ1 and if it is checked a new accounting (or updating the existing with the new tax values) has to be created. Is there any enhancement point to do the same. The screen enhancement for check box as well as for the new accounting document creation.