Compare the companies that work best in each region, what their price really includes, and where paying a little more makes the trip easier.
Most rental brands belong to a few large groups and often share cars, counters, and parking lots. A cheaper brand may provide the same car with stricter terms. Compare the final price, pickup location, excess, and deposit — not only the daily rate.
Not looking for a car to drive yourself? Private transfers covers the fixed-price, driver-included alternative — the aggregators, the airport specialists, and what the premium over a taxi actually buys.