The place was exactly like the listing. It was a great little place, tastefully done, clean and easy to check-in. There is no parking right outside but we had no trouble parking for free on street 100m away (it was low season). The little yard area at the back was sunny in the morning with a shaded area which would be nice for breakfast. The host left useful local guidebooks in the apartment and some good suggestions in his guidebook on Airbnb.
Mattinata itself is a lovely little town that seemed more local / real than more touristy spots. I would recommend over Vieste.
Overall it was great and good value. Highly recommend.