Housing scam

I am searching for apartment to rent. I recently viewed in person an apartment that looked great, but there were about 10 more people on the viewing. I talked a bit with the owner who stayed in the street near the house with a list of all visitors, and explained my interest. After viewing, I send the copy of passport and detailed that I am very interested, have sufficient salary, and would be happy to sign a contract. At the same day in the evening, the landlord messaged me telling that I was selected among other candidates and send me the contract for signing. The next day, he asked me to sign the contract by afternoon. It seemed suspicious to me due to tight deadline. I noticed there were typos in the contract with the move-in dates, which I asked to correct, and the landlord corrected. I also asked him to verify that he is the owner, show me energy certificate, and confirm that we will sign handover protocol of all items in the apartment before moving in. He ignored the handover protocol (did not comment on this in his messages), sent me Wohnungsgeberbestatigung as confirmation that he is an owner (although it was just hand-written by himself), and energy certificate which expired 8 years ago. It looked suspicious to me and I ended the conversation without signing. Was it indeed strange behavior or I was overly cautious?