[Samba] Fileserver and other questions

[Flávio Silveira]

Good evening,

   I have a Windows 2003 Server setup as workgroup with one big share 
that I want to replace it with Samba.

1- Is it possible to have shares per department? Let's say: a share for 
Sales users, a share for Administration users and so on, so that files 
and folders are only visible for each group. If so, how can I accomplish 
this? Also, is it possible to give read/write permission to just 
specific files on a read-only folder?

2- I'm planning on using Debian Jessie, which comes with Samba 4.2.10 
and it seems impossible to backport 4.5.2, is it ok?

3- Any documented issues with Windows 10 Professional with that setup?

On a different matter, I plan to migrate this to AD or at least Domain 
somewhat soon, for that I plan to contact one of the companies listed as 
Samba Official Support for my country.

For that my question is: How can a company get listed there? Is there a 
certificate or something?

My concern is how can I know they have enough Samba knowledge, but 
perhaps I am being too careful.

Best regards to all,
   Flavio Silveira