The majority of people are good and as everyone said people you know can turn out to be murderers so there is risk everywhere. Couchsurfing offers a lot of precautions, people get verified and you can give references once you have met or stayed with them. You can tell a lot from a person't profile and you can chat to them before you stay with them. I never stay with someone that makes me feel uncomfortable or that I am not 100% sure about. It is an amazing experience. It doesn't matter that it is free, I could afford to stay in a hotel, but I choose not to. I get to meet new friends everywhere I go that want to share their home with me! It offers travellers the opportunity to give back to the travelling community when they are at home. I have stayed with people in Korea and London and hosted or met for coffee with dozens of people and have never had a bad or even uncomfortable experience.
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