Hi! If you don't want to leave your Notebook/PC powered on all day (because power consumption), you can buy a "Mini PC", with an Intel Celeron J1900, like
this; or a cheap Windows "Tablet PC", with an Intel Atom Z3735G, like
this or
this (if you choose another model or brand, just be sure it comes with Windows installed and not with Android).
The "Mini PC" has a better CPU, uses a normal SSD 2.5" Hard Disk (of 500GB or 1TB), but it comes without a display so you will need a monitor to configure it, and then you can control it through a VNC connection. It also comes with a LAN port (which is more convenient for you configuration).
If you choose a "Tablet PC", it's cheaper and it has very low power consumption. It's ready to use and the only drawback is that usually comes with only 32 GB of disk space (about 20 GB of free space, if you take in count the operating system). It also doesn't have a LAN port (so you will also need a WiFi router, in case you don't have one).
I hope you find this information useful...
Cheers,
Leo.-