Cappadoccia to Antalya?

That's far enough apart that you should fly. A drive will be long, many times on paved two lane roads, and will require that you drive over the mountains down to the coast. The bus will probably be 8-10 hours (guess). A car will be faster, but more expensive. I know that Turkish Air flies from Kayseri to Antalya. You'll have to check prices, but I'm guessing flights will be $100 to $200 one-way.

fly is more expensive but will cut your bus ride time significantly. the bus ride is not bad but 12+ hours ride is not easy. i wouldn't rent car simply because the bus ride is cheap enough and i don't have to worry about getting lost. the long distance bus is actually pretty good, likely beyond your expectation if you haven't tried it yet.

One advantage to driving, though, is that you can stop along the way. Well worth visiting are the caravanserai, some of which have been well restored, at which travelers stopped along the Silk Road. Also worth a few hours (if not more!) is Konya, with spectacular mosques and the Mevlana Museithe mausoleum of the founder of the Whirling Dervishes. Visiting Konya was one of the unexpected lighlights of our first trip to Turkey. Closer to Antalya, Perge and Termessos have Roman ruins that are worth a visitthe view from the mountaintop at Termessos gives a stunning preview of the Antalya coast. One thing to keep in mind is that many Turkish car rental places will let you rent one-way without a drop charge, which makes car rental a cheaper option than it is in many other countries. You would have no problems navigating the routeit's a straight shot on good quality roads. Most of the way, you are driving on a high plain, and the road is well sign-posted. Frankly, you probably don't even need a map, though I like having one when I'm driving, if only to let me know how close I'm getting to where I'm going. Time-wise, flying is the best option; moneywise, bus is the best; experience-wise, driving is the best.