Ortigia is a magical place and Concetta's place was indeed magical as well, with the view as good as advertised.
Concetta was able to accommodate us as we pushed back our check in time a bit (due to a cooking class taking a bit longer than expected). Concetta and her husband even drove me to the main parking lot at the edge of Ortigia so I could retrieve my rental car. They had parked near the apartment and suggested that my girlfriend guard the parking space while I drove back from the parking lot. Success!
They had a binder with maps and a general Ortigia guide which was very helpful.
Finally, there is a small coffee shop across the street to the left of the apartment that is great for a quick espresso and pastry. Concetta's apartment is very central to everything - with the market maybe about a 7 minute walk.