$3k pays for a 1U server with a 32 core 2.6GHz Epyc 7513 with 128GB RAM and 960GB of non-redundant SSD storage (probably fine for build servers).
All using server CPUs, since that was easier to find. If you want more cores or more than 3GHz things get considerably more expensive.
Not that they are bad and would not be way better than what they have, just that I though the parent was quite the optimist with his Zen4/Zen5 pricing.
Had then some fun adding roles/groups support (not yet merged).