Advice for a cheap raspberry pi VPN server

I’m thinking of getting myself a raspberry pi for a VPN-server, but I dont know if I need some decent processing power. Would a pi zero w be enough for such a project? If not what would you recommend?
Thanks for any advice!

Depends entirely on your requirements. How much throughput are you expecting?

The PiZero being WiFi only (without getting a USB NIC which starts to bring the price so close to a regular RPi that there’s no reason to bother) pretty much takes it out of consideration right away.

Check this out VPN on rasberry pi

How fast do you need the VPN to run?

If you’re planning on using VPN only for remote administration or low bandwidth requirements then a RPiW would work. For anything requiring high bandwidth, get at least a RPi3B

If you have access, look at your Router for VPN capabilties. Might be cheaper/easier/better.