if you just want to receive Lightning tips, Neutrino lets you run a self-custodial node on something as small as a Raspberry Pi. It operates as a light client, so it skips the heavy block storage entirely and just pulls the headers it needs to verify your specific channels. Super cheap to set up and runs just fine. I've been running my own Lightning node with an intact channel on a Raspberry Pi 5 for two years now, using it frequently without any expensive enterprise gear. https://github.com/lightninglabs/neutrino