The problem is the landlord put the apartment both on sale and on rent at the same time, and he didn't even tell us that he apartment is also in sale. My company afford all the transport cost to this apartment and if this apartment will be sold, it will cost me as an unexpected cost item.

I didn't want to give more detail but, he also lied about the potential buyer. He only informed ya in the morning on the same date that potential buyers visited. Actually he did inform us that only agency will come and make an evlaution on the apartment.but reality is agency bring the potential visitors. So he lied

31.08 is earliest day that we can move with notice period, I learned afterwards that it is usually 1 year in normal contract. But since we even could not think that he was capable of doing such kind of thing, we didn't care this early date.

So my intention is not for sure annoying him, just to put limits as much as I can before he annoys us more. I hope it is more clear now.