I hold every single day, in my lovely picture frame.
I look a hundred years old, but I was built on the spot.
You might say I'm weak, and I'm four times over the hill.
Sometimes I take the elevator from the ground floor, not to be confused with my friends next door.
Having a look at the title will give you the conclusion, or is it there only for confusion?
Here's my friends' number 0 1 14 8 21, if you call you should find at least one.
My friends are hiding in some words, I think there's something backwards.
What am I?
The first four lines of the riddle should direct you to some answers. The next three lines are there to reassure you that the answer you've got is the correct one. If your answer matches the meaning of the last three lines then you should be right. As an additional help, I've added ellipsis (...) to the title.
EDIT : To be fair here you are all giving me very reasonable answers. As I said in the hint, this is an ambiguous puzzle, and when I created it I didn't think that someone would solve it, that someone would come up with the solution to this problem, as it requires some knowledge and a lot of scratch work to see if your answer is indeed correct. I think I did a good job at hiding the answer nicely. So if no one finds it I will accept the closest/nicest answer :)