The taxis in Correlejo are so cheap it's ridiculous! We stayed at the top of the hill, facing inland and a taxi from the centre of town cost 2.30 euros (but I always gave the cabbie 3 euros.)
There are at least two ranks in the town centre but you can also wave down an empty taxi as they drive by - and it seems every third car in Corralejo is a taxi! The cars are instantly recognisable - white with blue details. They are always kept clean inside and out but you may need to ask for a rear window to be opened as they can be pretty hot in the back, even in the evenings!
We took a taxi from our hotel to the Dunes and it cost just over 5 euros. We went to the rank outside the Riu hotel on Flag Beach and it cost the same back.
BTW; Most of the drivers are polite and helpful, but you do get the odd grumpy so-and-so. Same as everywhere, I guess!
Hire a car, The roads are better the home and are easy to drive on, no traffic lights only lots of roundabouts Why who knows. The best way to see the island and to visit all the local villages away from all the tourist shops and bars.