A mini PC is a solid option for a home server. They're small, relatively cheap, and low-power. I use a mini PC as a home server, but there are several things that my old Dell OptiPlex PC does better.
Dell's OptiPlex 3000 series of desktop PCs is aimed at businesses with modest computing needs. An information kiosk might be one use case for the OptiPlex 3090 Small Form Factor (SFF) desktop reviewed ...