rent a car for entire trip VS renting and droppng off at each loaction

I have not rented in Europe, but I have read that at least some rental-car companies do not allow their cars to be taken on ferries and that some of the others may charge extra for the privilege. I do not know how prevalent those scenarios are, but are you sure the cost you have discovered for Option 1 is the total cost, including any ferry fees that might apply?

Budget flights are sometimes available to the islands; traveling one way by air might save you some time.

Most of the islands are small and many rent ATVs to see the islands. The port cities are also walkable. Car rentals are best left in Athens.

Definitely just do the single rental from Athens; the airport is most efficient. We have always done this when traveling from the mainland to the islands. You will save a lot of time and headaches. Most especially when you disembark from the ferry, you won't have to walk or take a cab to the car rental, then wait in line, eating in to your time to check into a hotel, relax, sight see, etc. Also, you will appreciate the ability to spread your stuff out in the one car--water bottles, sunscreen, tissue boxes, snacks, stow your luggage before hotels are available, etc., and not have to completely clear it out each time you turn it in only to do it all over again in the next car.

Assuming you can find a car rental company to allow it, not only is it unnecessary and expensive to take a car off the mainland with you, but there are lots of car rental agents on the islands that will be happy to deliver a car to you at the ferry port when you arrive.

Really, how to find these companies ? I was using expedia, should be looking somewhere else ? That would be really convenient if they get the car to us.

Here's how: Just do a google search for car rentals on an island or in a mainland town and if the website doesn't mention delivery to the port contact them to ask.

On Santorini I always recommend Vazeos in Oia, Tony's in Firostefani, Spiridakos in Fira and at the port, Motor Inn in Kamari Beach.

Thanks, that was a lot of GOOD tips. I will be doing that then . WIll try local companies, and will call the names you gave me . I saw some comments of local companies being thugs but since u all have tried these before, I should be good I guess.

For Naxos try Fun Cars, They have a location right at the ferry port. We first rented from them in 1996.
However if you are staying in Naxos town you really can't use a car at all.
We generally stay at St George beach. Its actually part of Naxos town. Everything is within a 15 minute walk. We generally rent a car for 1 to 3 days to explore the island interior. Thats the time to rent a car. Fortunately there is free parking near St George beach.
One tip would be to rent the car in the evening. Park it then you will have it first thing in the morning. We have arranged car pick up at 9am but consistently with paperwork, car cleaning and Greek pace we don't get going until 9:30 or 10.

Thanks Stanbr, you saved me time, exactly what I was going to say ... glad u are back home from Hawaii, and dispensing your usual good advice; others of us had to work harder while you were off gallivanting!

Cars on the island become very close to be worthless. Taxis are very available and you can do a lot of traveling in a taxi for what you will pay for a rental and fees.