1. Controlling the transition from Pending to Approved
You can set the permissions as such:
That way that user will be able to save a Purchase or Sales Order but when they go to Approve it, Megaventory will ask them for a location. They are not able to write at that location so they will not be able to Approve.
Therefore, the Approve step will have to be completed with someone who has more permissions. Note that for the privileged user to do that they will have to take over that order from the less privileged user.
2. Controlling the transition from Approved to Received/Invoiced
You can take from a user the permission to access Transaction and Invoice Documents like this:
That way they will be able to Approve (see above case) but they will not be able to decrease stock or invoice:
Again, a more privileged user will have to do the Ship step.
3. Controlling transition from Received/Invoiced to Closed
This is not possible.
The equivalent points are valid both for selling and purchasing.
Note that whenever you take permissions from a user the corresponding action has to be completed by someone else. As such, although security and error-checking go up, delays and complexity increase. So that is all a trade-off you may want to consider.
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