I bought mine on backmarket, they act as a middleman. You buy from a repair with a minimum six months guarantee or beyond. If it stops working, you can send it to repair. Batteries are guaranted to be at least 70% original capacity or have been replaced. There are different grades from scratched to pristine. Not sure they operate in your country though. Getting a former flagship phone for 150 euros with a CPU just as good or equivalent to a new phone of the same price seems worth it to me. Plus it's nice not to have to worry about that expensive thing in your pocket.