Accommodations near Lisbon A.P.

We will be flying home from Lisbon on 10/13 at 10:00 AM. We will drive back to Lisbon from Porto on 10/12. I am concerned about the logistics of where to stay, returning the car and getting to the airport. Options: 1. return the car 10/12 in Lisbon and take cab to A.P. the next morning 2. stay in hotel convenient to A.P. and return car to A.P. just before check-in
Please advise. Can anyone recommend accommodations near the A.P. We prefer character to modern conveniences. Looking for moderate prices.