Hey marmeladko,
That's a great question! Reviews are a critical element of maintaining the quality of hosts and experiences within our community, so our process will ensure reviews which are fair and unbiased.
All reviews would not require approval before they are posted, to ensure they're a fair representation of people's thoughts. The only exceptional cases of reviews requiring further checks would be those reviews that contain certain 'red flag words' which make serious or libellous allegations. These will require immediate escalation to, and attention from the operations team.
Our Dispute Resolution is also driven through reviews, where over 50% of people who attend an experience are required to corroborate whether an experience was misrepresented by a host, for a refund to be triggered and for a host to be reprimanded. There is more info on dispute resolution here, if you'll find it of interest - https://medium.com/@Pally/dispute-resolution-within-the-pally-ecosystem-538093af98d