The coach 111 is every half hour, takes 20 mins to Los Cristianos, as stated 1.85pp. Greedy taxi drivers will charge what they think they can get away with. We have just been and used the coach, mad not to. Our friends used a taxi to LC, they were charged 26 euros, gave a tip as well, 28euros in all. Yes nice to have a nice car to ride in, dropped off at your door. You can hire a car for 3 days for 60euros. May as well do that and have the use of a car for 3 days.
Whatever you do decide, enjoy your holiday.