> Its an older apartement building though, i dont know if it makes the work harder

Depends on the building but it might make it easier depending on the door and lock.

Funny enough, years back when I lived in an older rent stabilized building in Queens my roommate locked herself out & everyone else was out of town. So she called a locksmith (paid something like $175 upfront) - Apparently the locksmith used a plastic bottle & opened the door in a few seconds. I never got around to practicing that trick but if you google around there's lots of youtube videos on that. Depending on the type of door you have that could be worth a try.