I moved my services a couple of months ago from a RPi3b to a second hand HP ProDesk 600 sff. You also have a Dell variant (Dell Optiplex SFF). These can be found for around €100/$100, don’t use to much electricity and are way more powerful than the RPi. Also, they use the x86-64 instruction set instead of arm which has better software availability. Let me know if you want to know the specific specs/version I have!
I moved my services a couple of months ago from a RPi3b to a second hand HP ProDesk 600 sff. You also have a Dell variant (Dell Optiplex SFF). These can be found for around €100/$100, don’t use to much electricity and are way more powerful than the RPi. Also, they use the x86-64 instruction set instead of arm which has better software availability. Let me know if you want to know the specific specs/version I have!