Yes, I did it quite a few years ago, needed another driver added so they could bring my car home and return to pick us up from the train station. Rang them up, gave them his details (drivers license etc.), paid via debit card and got an email confirming everything while I was still on the phone with them.
Please excuse spelling/typos. Apart from being a clot it turns out I had one on my cerebellum that's now causing various problems!