Vitaly,
That is correct - you either have to be 21 or over holding a full driving licence for over a year to be eligible for
short period insurance or be over 25 with eCar Insurance. Unfortunately, there's no other company out there which will offer you the temp cover you are looking for at the moment.
However you can ask somebody else (parents/friends) to bring the car for you from the seller and then arrange your proper insurance cover. Most people who are on comprehensive cover can drive another car with Third Party Only cover, so this will save whoever you ask for to purchase a valid insurance specifically for driving your car from the seller. Please ask them to check their insurance policy to make sure they are indeed insured to drive other cars though.
