A taxi from PMO Airport is approximately €80 and doesn't save you more than a few minutes. Have Daniele give you details about the private bus that runs every 30 minutes for €6 and drops you off 5 minutes (walking) from the apartment.
We use Airbnb frequently and occasionally a host stands out as exceptional. Daniele is one of those hosts who is very genuine and kind. He is always available and goes out of his way with excellent recommendations.
The apartment has plenty of space and is in a good area close to attractions. It was clean and was as described. Daniele and some reviewers mention the noise from the market below. We used a "white noise" app on our smartphones and easily drowned out the early morning noise. It wasn't an issue.
Safety was never a concern in this neighborhood, or anywhere in Palermo for that matter.
I highly recommend you stay here. It was a great value.