Hi Tom,
If it is just two of you, then you do not need a server. Whether Windows or Mac, it is completely easy to set up a so-called peer-to-peer network that lets you share the files on one machine with the other or each machine with the other. (On the Windows side, this is easiest and most secure if you have a Professional/Ultimate version of Windows - NOT the Home version. On a Mac, it's just easy, period.)
Alternatively, you can just buy a "network attached storage device" - fancy language for a box with one or more hard disks and a network jack in the back that just shows up as shared storage on your network. Want one with a fast drive and gigabit ethernet interface.
If the two of you are considering running TeamWork, then your new computer should have good performance specs and ample memory / fast disk storage.
Also, if your computer just died, chances are that your router is old too. Consider upgrading to a gigabit router (under $50) as the data transfer speeds when your other computer accesses files on your new one will be dramatically faster. (The existing computer, if a PC, may need a gigabit network card added - cheap and very easy do it yourself thing.)
Cheers,
Karl
One of the forum moderators
AC 28 USA and earlier • macOS Sequoia 15.2, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB