StackSocial: AdGuard Personal & Family Plan: Lifetime Subscription $11 USD

Personal (3 devices): $79.99 -> $11 -> $19.97

Family (9 devices): $169.99 -> $11

There are free alternatives out there, I got this because AdGuard for Linux requires a license, for self-hosting whole home adblock.

Personal was also $11 yesterday but it went up to $19.97 today.