Can I rent a vehicle with 20 years old at San Juan Airport Puerto Rico?
Do you have a driving license at least 1 year?
Yes, I got my drivers licence when I was 16...
OK. First start to make a search...Then check here age restrictions per supplier:-
At STEP2, click on the link "IMPORTANT INFORMATION' displayed to the right of the car photo of your choice. This will open another smaller window and if you click on "DRIVER" you will see what age restrictions there may be and any associated fees. Try a few different car models / suppliers, as they do differ.