Vermine in Storage

Hi all here's a tip, I read once that if you place tumble dryer sheets around the inside of the van when you put it in storage the vermine will not enter the van as they don't like the smell. Well,  I have tried it for the last couple of years as I store my van on a farm, with no electricity for a scarer, so far mice chews on the van cover straps but nothing inside the van which tends to suggest it is very possibly true. Which ever way I must say that the van always smell nice when you enter it even after a long winter store.