I have only purchased new Macs, but I find that the total cost of ownership is lower than Wintel PCs.
As MecaSpanky mentions, the Mac hardware is more useful for a longer time than PC hardware.
Second, Macs have a bunch of free bundled applications (Pages, Numbers, Keynote, iTunes, Photos, iMovie, GarageBand) that are probably worth a couple hundred dollars for Windows users. Even stuff like an e-mail client, address book, calendar, etc. are all built into the macOS. Recent versions of Windows have integrated more of this into the OS, but really you needed to buy MS Office to get this functionality. Even today in Windows 10, it's mostly browser based on a standard install.
Then there are the intangibles. Those software packages and others are more tightly integrated with Apple's ecosystem and cloud services: notifications, data syncing, media purchases, etc. iBooks and its integration with iOS. Time Machine backups. The convenience of the App Store. Messages & FaceTime. Maps. Even the relatively weak Siri.
Another thing to note is the system administration load. Windows 10 is a very smooth user experience compared to earlier versions of Windows, but there is still a higher sysadmin and maintenance load with Windows than macOS. I remember when family members switched from PCs to Macs. All of a sudden, the calls for family tech support stopped.
Especially if you live near an Apple Store, you have the Genius Bar as technical support. With Windows you will bounce around various tech support groups and there isn't a standard physical place where you can bring your device and say, "it doesn't work, please fix it for me."
Trust me, I think Windows 10 is a very capable operating system and a very worthy successor to its predecessors. I have a copy running on a VirtualBox virtual machine (primarily to run Quicken).
But if I weigh owning a Mac over its lifetime and owning a Wintel box, I'd pick the Mac every time. At least for my purposes, I can run Windows in a virtual machine for the handful of tasks. I'm definitely not a gamer, but free VirtualBox is good enough for me.