I found quite big two insects in the unit on the first night. I caught them and took photos. I showed them to both the host and airbnb. I got a partial refund ~$1200. I have booked the place for 13 nights for ~$2000. So I lost ~$800 from this reservation. I had to get a new place on the day for the rest of my trip. Therefore, it was a total financial disaster for me.
Airbnb's agent response: "I don't exactly know the rules but you would need more than five insects to get a full refund."
If I found two insects on the first night, I am sure there are many more. However, I didn't want to stay any longer to take photos and show them.
Also, the host was very noisy late at night which was very audible from our unit. Had issues sleeping well.