Good afternoon! Are smoke detectors inexpensive? Recently, there was a fire on the 2nd floor in our house and I would really not want this to happen again in my apartment or for the neighbor's fire to move to mine. Therefore, I want to find a simple, inexpensive option for myself. We are not going to burn weekly. But seriously, you really need to think about security. I've heard a lot about ajax on the Internet, but I haven't heard reviews from real people on this forum. What do you think about it?