Hi there and welcome
I would advise on 2016, its the later version which means you will have a lot more time for using it till you need to update again.
It can handle multiple Pop email accounts and you can transfer your outlook data from any previous version of outlook
If you setup Office 365 you can still set up multiple pop accounts. Actually, all versions of outlook on the computer can do this.
You can transfer existing PST's and yes the multiple accounts can send and receive, no issue.
If you would like any additional information or assistance, please do not hesitate to let me know.
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