Maybe there are 5 conditions needed!

The one I am going after is not a javascript error but rather when a customer causes an error by not filling in a required field, for instance.

I fill out form, but leave required phone number blank. when the checkout page repaint with the error on top saying "phone number is required", I want the page to automatically trigger a quote recalc or.. ideally, display the old quote with the custmers choice from the previous screen still selected.