Hi to everybody,
i stumbled in a little problem, i didnt know where to find answers.

I'm the owner of a little company (5 people) and we work in the media.
I'm thinking of building a NAS to create a space where we can put all the files we need to work with, and so everyone one of us needs to access a file can just open the folder of NAS, search what he needs and open it.

We often works with projects files such as .psd, .ai, .prproj and would be nice to not transfer the files to our pcs, work on them, and then retransfer them on the NAS but just open the files directly from the NAS.

Now comes my doubts:
1) Is it possibile to work directly on files with a NAS?
2) If it's possibile how powerfull it needs to be to let 5 people work on files that are stored in it?
3) Since the NAS is ony use to access the file, but the work on the file will be done in our pcs, the computational work will be done by the pcs or the NAS?
4) If nothing of this is possible with a NAS, with system would you raccomend to do this kind of work?

Thanks to everyone that will lose their time to read and respond to me, and i'm sorry about my bad english, non native speaker here.
Every suggestion will be appreciated!