Looking for low power devices for selfhosting

Hi friends. I'm a newbie in self-hosting, though I've been managing (virtual) linux servers at work for a couple of years. I'm completely ignorant on the hardware choices out there, hopefully you can point me to the right direction.

Here are my requisites:

• Low power consumption, I plan to have it connected 24/7 and I'm kinda concerned on how much it will impact the electricity bill
• Ethernet port, preferably gigabit but whatever
• Graphical performance is not important as I don't plan to connect it to any display. As long as I can ssh into it, I'm good.

Services I plan on installing, for starters:

• casaOS
• pi-hole, or equivalent
• Home Assistant
• Kitchen Owl (nice to have)
• Paperless-ngx (nice to have)

I live in europe and my budget is around 80 euros or so. Thanks in advance!