Automatic email notifications can be switched on in the edit window of each supplier, in the Supplier section in the Administration settings. Email notifications can be tailored depending on the [...]

Yes, at any time. Even if certain Purchase Orders might have already received their final approval.

Yes, again you can select as many users as you would like to enter account numbers.

You can decide whether the user is allowed to see all Purchase Orders, just their own, or the ones from the department he or she belongs to.

If the creator of a purchase order has been deleted, their purchase orders will remain unchanged. However, if a user has purchase orders awaiting approval, then these will be automatically [...]

Yes. If this user has approval rights, make sure you install a new user for that approval level first, and then delete the other user.

Yes, you can select as many administrators as you would like.

An Administrator can edit the administration section of the purchasing software, the User cannot.

If the pending Purchase Orders have received all approvals except the last level, they will automatically switch to final approval once you delete the last approval level.

Yes, but first make sure no user is assigned to that approval level.