If you are using software from Microsoft or Apple, then you probably do have to pay for it, and for every user you have in your business.
Did you know that there is probably a free and open source software package that can do the same, or better, job?
It is available for pretty much every operating system (OSX, Linux or Windows) and covers a huge range of software types.
For a great replacement for Exchange Server, try Zimbra.
For a great replacement for SQL server, try MariaDB or Thunderbird
For a great replacement for IIS, try apache or nginx (Microsoft even use these now)
For a great replacement for Office, try Libre Office or Open Office
Just look around or ask us. There are thousands of better options than paying good money for buggy software.