domain controller. The rationality of its installation with a small number of users. Should I start the installation?

Question

Active Directory

Good day gentlemen.
Do not judge a sysadmin who is starting his way strictly, as the following questions may strike you with stupidity and obvious "nonsense":
1. Recently I moved to another office and there is no security policy implemented, or rather, nothing has been implemented. Naturally, I decided to improve the situation. To come to mind only the installation of the Domain Controller and the distribution of rights to users according to group policy.
But there is one caveat: there are about 40 users in the network (there will be a maximum of 50). Is it worth it to do what you want to do?
2. The second question immediately arises: should the mail server be configured on MS Exchange? (Yes, yes, "they" ask you to set up your mailer) Or do you need some third-party software that is simply installed on a regular PC under Windows 7?
Perhaps some of you have come across such a situation, please advise.
Thanks in advance :-)

Answer 1

The domain is not about security issues. It's about ease of management.
Group Policy is not a tool for assigning user rights. As the manual says: "Group Policy is the easiest way to configure computer and user settings on networks based on Active Directory Domain Services."
You need to set a domain, but I would recommend first deploying some domain in a virtual machine and doing a few labs on setting up a domain and working with group policies. To better understand what it is.
Exchange is also not just a mail server. If the question arises "to bet or not", then the answer here is exactly one - "not to bet". To organize mail, if you really really want your own, it is better to use solutions like Postfix + Dovecot. Well, or at worst - some kind of Zimbra.

Answer 2

according to the "standards" 10 users is already a CD. forget about the ekschend. look at his requirements to get started. either on Yandex (Google) they drank mail, or something easier.

Answer 3

It is rational to start a domain or not - depends on the specific conditions.
Buy a license for the server, buy licenses for workstations and transfer to the "Prof" version, buy CALs, ...
Buy a computer for DC, buy a computer for a mailer.
Buy a mail server program, say MDaemon
Total about $15,000. Can you justify these costs to management?
Or is there no talk of buying licenses?