What to do if there are urine marks and stool marks on the floor of the main bathroom?

Find a steel wool ball and drop a few drops of toilet cleaner, gently wipe it a few times and remove it, I hope it can help you.

It's all neighborhoods, and it's better to talk to the neighbor again, or let the property put pressure on him again (water and electricity outages, etc.). If it doesn't work, have a lawyer come to the door and explain what's at stake. If it is not repaired, it can only be solved by law.

Since there will be a watermark on the wall between the bathroom and the living room, it means that there is a leak in the bathroom. It is estimated that the water pipe is leaking, or it may be a waterproof leak.

The inner wire connecting the faucet is not welded well, and the wall must be knocked off and re-welded.

There are two possibilities, one is that there is a problem with the glaze of the brick, and the other is that the wall tiles are not printed after taking a bath, but there has always been a seal, but it is usually relatively shallow, and I don't pay much attention to it.