i got a prescription for Vidalta for Sam, the vet writes on how many repeats you are allowed, mine did 3 for me, as he would then need to be retested to check he was still on the right dose. I think it was about £5, and then VEtUK wrote a reminder asking if I needed anymore (sadly he had been pts by then). A months worth of the 10mg Vidalta was about £12ish, i was paying £22 at the vets, so I did save - if your friends vet did a 3 month for £15, it is only £5 a month, and if she is saving £10 on the meds, it is worth it.