Several options depending on your plans.
Rental Cars
Probably the best way to get around the island although in crowded areas like Fira and Oia it can be a bit of a challenge to park. In all other areas including Kamari, it is very easy to park and you can pretty much park anywhere there is not a “no parking” sign. I would go small on the rental since it is easier to park and drive on some of the small roads. If it is only two, I would rent a mini vehicle like a Fiat 500 or a Panda. If you have 3 or 4, you should stick to an economy car. Of course, I am assuming you will be driving into Thera (Fira) or Oia, if not then you can rent a larger vehicle, but don’t go too big. The best place to start is https://www.rentalcars.com or https://www.carrentals.com. You likely will need an International Drivers License to rent, you can get them at AAA for $30 and you don’t need to be a member. Do not drink and drive, the legal limit in Greece is 0.05 blood alcohol.
There is a great video on driving in Santorini: https://www.youtube.com/watch?v=f_LY6vt8s4o
Quads
You can rent a quad and it is legal to drive them anywhere on the island. This is a fun way to get around, but it can be pretty dangerous so be cautious. It is about the same price as a car, so I would recommend a small car over a quad. You can also rent one just for a day to get around to some remote areas of the island. If you do decide to rent one, there are typically two sizes; small (up to 300cc) for a single person and large (450cc and up) for two. I would recommend you get one with a backrest if you rent the larger version. You may need an International Drivers License to rent, you can get them at AAA and you don’t need to be a member.
Do not drink and drive, the legal limit in Greece is 0.05 blood alcohol.
Scooters
Scooters are available, but not a safe option, and most places will not rent them to you unless you have a motorcycle license.
Taxis and Uber
Uber is there, but from what I read it is not very dependable. If you choose not to get a car, you should arrange travel with your hotel, who can set up a taxi to pick you up at the airport.
Leo’s Transport Service
I will rent a large vehicle and will share my phone number with anyone who may need a pickup or a ride. (860) 416-1240. I will be at your service, but there will be times I may not be available. The best way to contact me on the island is using WhatsApp or Facebook Messenger.
Busses
You can get to a lot of points on the island using busses, keep in mind that they all go through Fira. So if you want to go from Kamari to Oia, or Firostefani to Oia you will need to go through Fira. More information is here https://santorinisecrets.com/santorini-bus-schedule/ and on Santorini Dave’s site https://santorinidave.com/santorini-buses. The buses are very clean and accept cash only, they do not give change, so you will need exact change. the cost of each leg is 2 Euros and some Southern beach routes are 2.50 Euros.
