I got a mini pc and ran pfSense back in the day. I’ve been using pfSense ever since, though I’m now on their hardware (which costs more than your stated budget).
I agree with folks recommending Ubiquiti, but I’m also barely literate in the aspects of the market that matter. I just recognize the brand as trusted and we used their devices at a job I had.
For some reason, I have a negative view of Mikrotik - as though I’ve read something damning in a security-related article about them - but I can’t back that up. If I did, it was only once.
Stay away from TP-LINK. I had one of their devices and it was garbage.