Please find useful website links for flights and car hire. 

Whilst we do not provide car hire; on our trips to Portugal we use one of the following car hire rentals, the car is collected directly from the airport and returned to the airport. (No hassle getting on and off buses to a storage depot when collecting or returning your car).  Their prices are very reasonable and due to the prices and service we do recommend them, please see links below.
When you link on to their site, just fill in the email form and they will email you with a quote for your vehicle hire, if you wish to go ahead you simply respond to their email.