1. When the suspecious new listing which is much cheaper than all the others, try reverse search images:
A:https://tineye.com/
B:Click on the image>swearch google for image
C:https://chrome.google.com/webstore/detail/noobox-search-by-image/kidibbfcblfbbafhnlanccjjdehoahep?hl...
(noobox helped me found the most)
2. Contact the host with some regular questions.
3. Look into the details of the pictures, different plug (et. UK listing but images show US plug)
Scam-A:
Living in a Fantastic Location of Reykjavík
https://www.airbnb.com/rooms/30552235?location=Reykjav%C3%ADk%2C%20Iceland&adults=2&check_in=2019-01...
Scam A suspecious reasons:
1. too cheap for its location
2.New listing
3.Don't responce to message
4.too bright, and weired chimeny display in the house which Iceland don't have
Fact
Legitimate: (Gamla stan, Stockholm, Sweden)
https://rus.worldtourismgroup.com/11-stockholm-s-stunning-airbnbs-81537
https://www.airbnb.com/rooms/21439482?location=Gamla%20stan%2C%20Stockholm%2C%20Sweden&adults=1&gues...
Comparison: