And you can upgrade in future to match your actual needs instead of wasting money trying to front load costs for no benefit.

You can buy a “lightly used” Dell Optiplex with 8gb RAM for like $40 which will cover all your self hosting needs today.

Yup, and if you need something powerful by today’s standards you can grab a mini pc like this (1) one. Install arch or whatever, and go. Install k8s. Run a cluster of 16 nodes on this one little machine.

(1) https://www.bee-link.com/products/beelink-gti12-ultra-i9-129...

What's its power consumption?

Mini PCs/uSFF with an Intel i5 6500 generally use about 8-10W with low to moderate load, WiFi disabled.