The lowest number on a rental search is rarely the lowest final price — it's usually the base rate before insurance, taxes and a deposit-holding fee get added. This page sorts by the total you'll actually pay, so "cheap" here means cheap at checkout, not cheap in the ad.
Off-airport pick-up locations with a free shuttle consistently beat in-terminal counters on price for the same car category — those offers are marked so you can weigh the saving against the extra ten minutes.