Most people treat car hire as an afterthought - something to sort out once the flights are confirmed and the accommodation is locked in. That instinct is costing them money, sometimes a lot of it.
Rental car pricing is demand-based and inventory-limited in a way that airfare often isn’t. Airlines can sell the same seat class across hundreds of flights; a car hire depot in Reykjavik or Dubrovnik has a fixed number of vehicles. When those vehicles go, the remaining ones jump in price - and they often double or triple in the final two weeks before pickup. If you’re flying into a popular destination in July or August and you haven’t touched the car hire situation by April, you’re not getting a deal. You’re getting what’s left.
The sequence most travellers use is backwards
Flights first, hotel second, car third - that’s the default order because it feels logical. Flights set the dates. Dates set the hotel. Car fills in the gap. But car availability doesn’t care about your logic. In smaller airports and island destinations especially, the rental fleet is genuinely finite. Santorini, the Faroe Islands, rural Sicily - these aren’t places where another 50 cars appear because demand increased. You’re competing for the same pool everyone else is.
A better approach: once you’ve roughly decided when and where, check car hire availability before you confirm anything. It takes ten minutes and tells you immediately whether supply is tight. If prices are already high in the planning stage, that’s a signal, not a coincidence.
What to actually book through
Skip booking directly with the rental company at first. Aggregators like Rental Cars or Discover Cars let you compare across suppliers, and the prices are often lower than going direct - particularly when you factor in basic insurance bundling. Read what’s included carefully. Some rates look cheap until you add the collision damage waiver, which is almost always worth having.
Pay with a credit card that includes rental car insurance as a benefit. Many do. It won’t eliminate the need to understand the depot’s own policy, but it can serve as secondary coverage and reduce what you need to buy on top.
One thing that doesn’t get said enough
The cheapest rental isn’t always at the airport. City-centre depots sometimes price lower because they’re competing with public transport, not just other car hire counters. Worth checking, especially in larger cities where getting from the centre to the airport is straightforward anyway.
Car hire is the one part of a trip where booking early has an almost unconditional upside. The pricing rarely goes down as departure approaches. Plan accordingly.