While you are on the site, in your browser find and click "Add to Home Screen" A CGN beaver app icon will then be created to your phone that is directly link to the site.
Note: This feature may not be available in some browsers.
Private sale? No. It's handier if you have their name and PAL number and phone number when you call in to complete the transfer.
Business sale? No. You may not even get a reference number.
I got my reference number from Marstar by sending email and asking for it as per Marstar instruction. Have no idea about other vendors although I guess they would send one if you asked for it.