"According to the law the house is now ours."
Translation:Yasaya göre ev artık bizim.
I think it is only anymore when the sentence is negative, that is, something that used to happen is not happening anymore. "Artık we don't do that, sorry." In English: we don't do that anymore, sorry. The opposite of this is when it is a positive statement. "Artık we do that." In English: we do that now.
Sooo, how should I say it if I want to emphasize that it is ALREADY ours? For example, we are buying a house. We paid, and signed the contract. And the seller says: "I will remove my stuff today and give you the keys tomorrow, and then the house will be all yours". To which I would say: "Well, actually... according to the law, the house is ALREADY ours." It is slightly different from saying "it is NOW ours", because it emphasizes the fact that it happened earlier than (the other party) assumed. It already happened. Maybe... "şimdiden" would be a good candidate in this case? Or "zaten"?
Bizim and bizimki are not interchangable. Bizim is usually follewed by naming what is owned "bizim koy" "bizim araba" etc. Bizimki is used when the name of the thing owned is already eastablished in the conversation and it does not have to be named again. You can not start the conversation with bizimki. It has to be identified first with bizim......something. Something here is the noun. Afterward, bizimki can be used, but the "ki" turns bizim into the noun in the sentence. Hope this helps