HORRIBLE EXPERIENCE: My best friend and cousin sister were visiting and needed a ride back to Columbia Metro Airport for an early 6:00am flight. Called the day before an arranged a 4:15am pick up, giving address and neighborhood (we are in Lake Carolina). Cab driver called at 4:17am for directions - she said she was at Exit 18 off I-77. I tried to tell her directions via I-77 to Exit 24/US-21 toward Kelly Mill Road. She said she'd call back after exiting interstate to write down full directions. Called back around 4:23 and said she was on I-20 about a mile from Clemson Road - I started asking how/why she got on I-20 when I told her to Exit US-21 of I-77 North. Was about to tell her alternate directions via Spears Creek Church Road but with the look on my friend's face and the clock ticking down towards their flight departure time, I told her to forget about coming here. I had to give my cousin & friend our personal car to get to the Airport and park in the paid surface lot. Luckily I work at the Airport so I could pick it up easily, but I still had to waste 20-30 minutes out of my work day to pick up the car. This was the worst taxi cab experience of my life. I don't expect hyper-efficient cab service like in New York, DC, or Chicago, but I do expect the cab driver to call well in advance if he/she does not know directions, and to actually listen to me when I do give directions. Will never, ever use or recommend Carton's Discount Taxi ever again.