Raspberry Pi 4 with 4GB RAM is the recommended minimum specs for running a node.

You can have a full Bitcoin node, block explorer for privacy an Electrum server and even a Lightning server running on that to get by with a 1 or 2TB SSD

However, a refurbished computer like a dell will be far more powerful and have more RAM to support running other bitcoin apps if tiny physical space is not the main concern.

See Raspibolt.org or raspiblitz.com or MyNodeBTC.com