For a smooth experience, I'd recommend booking your car rental at Tenerife Los Rodeos Airport in advance. This way you can compare prices and vehicle options from various providers. Many companies have counters in the arrivals hall. You can check available options and rates on this site https://getrentacar.com/en-US/spain/tfn-tenerife-north-airport-los-rodeos-airport--5. Just remember to bring your valid license and credit card!
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