Hey Karim,
Hope my message finds you well. I am a Superhost living in Athens, renting a studio in Monastiraki, and I had been looking for a trust worthy management company for a long time. A couple of months ago, I found Nexus Getaways, which offer more services than any other in the market (eg. personalized verification of guest on check in and personalized key collection on the check out, etc.) and they only charge 10% for full management! Since then, I spend no more time on running my apartment on Airbnb, and I am already fully booked on April, May and most of June and July.
I am really satisfied with their services and I suggest you try them!
Best regards,
Nikos