I've done your Expert Series through 13 and looking back through my notes, whenever we've used DLOOKUP, it's only to display data on a form.  Is it possible to use DLOOKUP to pull information from a table but to still save it in another table?

Here's my example.  We're in an Order Form.  You select a vendor through a combo box linked to a Vendor Table.  Some Vendors have Blanket POs and others do not.  

In the Order Form, if a Vendor is selected that has a blanket PO, I'd like that number to fill into that PO field.

But, I can't set the control source to a DLookup because I need to save that value in my Order Table.  And, I need to be able to edit it.  Even if a vendor has a blanket PO, that may not be the PO we use for that specific order.  Setting as a default doesn't work because the vendor is selected mid-form.

Another question in the same form...I have a few different types of transactions (selected through an option box) - Donation, Invoice, Misc Expense.  

If donation is selected, I'd like another field to autofill with specific information.

Basically, both are a question of autofill based on a selection made earlier in the form.  Is this possible or am I way over my head?