I make these suggestion during all conversations about PiHoles: Use Class A2 SDmicro cards (they'll last significantly longer... particularly if you keep logs)

I make these suggestion during all conversations about PiHoles: Use Class A2 SDmicro cards (they'll last significantly longer... particularly if you keep logs). There are additional 3rd-party installations which can write into RAM, but IMHO it's easier for most new users to just buy better NANDs. Set up more than one physical Raspberry Pi, running multiple versions of PiHole software on multiple IP addresses. Have your main DHCP router auto-issue DNS information for your "most permissive" PiHole, with a minimal list of choice URL-blocks (e.g. pagead2.* , doubleclick). Individual clients can then manually change DNS server to 2nd (3rd... 4th...) PiHole(s) which are each more-restrictive. This allows non-technical users to still browse somewhat ad-free, but also won't block banking/govt/etc for novices. As a failsafe, teach users to enter your router's IP as DNS x.x.x.1 [should they ever need to bypass local filtering, entirely]. I use sequential IP addresses [192.168.0.6, x.x.x.7, x.x.x.8, x.x.x.9] so it's easier to explain/teach my networks ad-blocking capabilities. YES, I understand that Pi-Hole allows different clients to follow different rulesets, but if you can afford to buy redundant hardware it's just so much easier to change the client DNS server information when a specific website isn't working correctly [due to erroneously blocked host].