Upon returning the vehicle, take some time to inspect it thoroughly both inside and out with the representative of the rental company and ask for an instrument of transfer to be drawn up to establish the condition of the vehicle. If some spaces are left uncompleted, scratch these out to avoid something being inserted in the vacant spaces later.
Try to avoid returning the vehicle outside the regular opening hours of the rental company. Should you return the vehicle outside the regular opening hours of the rental company, you cannot ask the representative of the company to inspect the car with you to record the vehicle’s condition (whether you have filled the tank, whether the vehicle has damages, or whether all the items are present (for example, the child seat), etc.). If this is the case, be ready to be billed for damages of the vehicle that you have not caused.
Should the vehicle have the damages, referred by the rental company, but you are sure these were not caused by you, these may have been made after you left the vehicle at the agreed spot and the representative of the company had not collected it. Unfortunately, you have no way of proving that you did not cause these damages. Therefore, it’s better to avoid such situations.
All the information is from the Estonian Consumer advice portal: http://www.consumer.ee/en