The reason why you might be having trouble finding a good policy is that is that, aside from standard 12 month policies, most temporary car insurance is reserved for the over 21s. This is due to the fact that drivers below that age are considered to be high risk by the majority of the insurance industry.
Despite the fact it will take a little more of a hunt to find the right policy, temporary car insurance for young drivers will generally feature the same level of coverage as more standard policies.
It is recommended by many experts that this kind of niche car insurance is searched for online. It could take a very long time to contact each provider looking for car insurance quotes, whereas the point of temporary car insurance is that is supposed to be flexible to the needs of the person who is taking it out.