We will be arriving in Chania on a flight from Athens. Staying at Marriott Domes which has free parking. A couple of reasons we are thinking of waiting to rent a car. There will be 4 of us, so even with just a carry on and backpack for each of us, we would need a mid size vehicle at least which may be harder to park than something smaller. Also, we are thinking we won't need a car the first day or two as we explore the old town area on foot, but for other excursions (botanical gardens, Rethymno) it may be more convenient to have a car. Taking a taxi to and from the airport saves us the time and hassle of picking up and returning a car at the airport. Thanks in advance for any thoughts.
The last time I was in Crete (two years ago) we rented a BMW X1 which is a smallish SUV and we had no problems parking it anywhere across the island. I wouldn't base your decision on when and what size to rent on potential parking spaces as it really wasn't an issue.
I am having a difficult time to find the location of Marriot Domes in Chania. I am going to guess its a newer resort which is likely just outside Chania city.
So that means you will likely need the car to explore the surrounding area and perhaps to get into Chania old town area if the walk is too far from the resort.
We have rented from Local car companies many times. If you want a recommendation Auto Rentals Crete is well respected. They will deliver the car to you where and when you need it.
I often suggest that renting a car is a waste of money because the first couple of days it will simply sit in the parking area while you explore Chania old town on foot.
For exploring the surrounding countryside a car is a great asset which gives you flexibility. I would go with your plan to rent the car once you are ready to start exploring.
I also posted this in another one of your threads, but driving in Hania (aka Chania) was a major pain, with one-way streets winding through downtown, and intersections where we couldn’t turn the direction we were trying to go. It took a long time to reach our hotel at the old harbor, although we were finished with our rental once we arrived in Hania towards the end of our Crete trip. Depending on where in the city you’re staying, having a car there (even if the parking is free) would be more of a problem than a benefit. Based on our experience (and we turned in our car on the street, once we got a place to park it), don’t get your rental car until you’re finished with Hania and are moving onwards.