Hello, I have a few questions regarding applying for the NIE. I have checked out the official sites but im a bit confused as to whats required

Can I use a Hostel address when applying for the NIE or must I have a rented flat/appartment with proof of contract?

Do I have to be registered on the population register before going to the NIE or can I do that later?

Do I have to make an appointment or can I just turn up on the day and wait my turn to see the agent?

If I have to make an appointment how long do you normaly have to wait before being seen?

Im ariving in Madrid on Friday 8th July and am hoping that I can apply for the NIE on Monday 11th.

Thanks