I will say shortly that this has been (and still is) the worst expoerience of my life.
The (supposed) landlord, mr. A.M. (a wannabe tennis player and a gambling addict) scammed me and other people forcing us to give him 900 euros cash (450 rent + 450 deposit). He used this money not to give the room he promised to us , but to pay his debts, leaving us without a roof in a snapshot. In the end, we all sued this guy and we are now in trial against him to have part of our money back.
From now on I'll speak in first person, this is the only common denominator between me and the other people involved in this scam business, so I'll start from the beginning telling my experience.
I was searching for a new room in Leiden in December. I found this apartment via a secure website, Kamernet.nl. The landlord, Artjom, answered immediately asking me if i was reallty interested and that since a lot of people were interested in the room as well, I should have met him ASAP to give him some money and freeze the room. I agreed, but on the condition that I would have visited the house first and signed a contract before giving him any money). I met him the day after, he was sweetand gentle. He showed me the apartment, he introduced me to the tenants, reassuring me that they would have freed the house by the end of the month and I would have lived with him starting from Jan the 1st. After that, he gave me a (real) copy of the house keys. I gave him the money some time later, in small amounts. After that, starting from the end of December he started postponing the day in which I should have occupied my room. Needless to say, I was desperate because my current contract with my former house was ending soon. After several weeks, I found out not only that he rented the same room to other people with the same tricks, but also that he was a gambler and had a lot of debts with other people he scammed in the past via ebay, and me and the other people involved, including the current tentants of the apartment, who feared him and his companies, started a long sue against him, after finding out that he wasn't even the real owner of the place and that he was subrenting it. He gave back to me just part of the money in cash, and only after I begged him, because I was without money to rent a new room. In the end the trial still goes on and he still owes me 600€.I never lived in the apartment, and to find him and ask for my money back made my next 4 months in netherlands a real pain. So NO, DO NOT TRUST THIS GUY AND ANY ANNOUNCEMENT YOU FIND VIA WEB FOR THIS APARTMENT, you are advised, always check the identity of your landlord before giving any money to him.