The location of the flat is excellent, smack in the nicest and safest area of Athens.
Also, the support and organisation by the team managing the premises was excellent and very rapid - the team is available on phone, WhatsApp and internet.
The flat is sizeable, and easily will accomodate four adults.
The only (minor) details for improvement related to the fact that the flat seems designed for rent and not someone's house, meaning that some of those tiny details that one only notices when "living" in the space could do with some improvement (such as a little blocker on the shower doors to make sure that the bathroom floors don't get flooded when showering).
The overall experience was outstanding and I'm sure that the excellent team behind Olala will make those small tweaks in response to constructive feedback from guests.