I'm just using the bare minimum amount of DDoS Protection out of the tier we use. We're a pretty small company, so we haven't been the target of any major DDoS attacks yet. That's why so far the basic DDoS is all we need.
If your company uses Cloudflare, then everyone in your environment inherits DDoS protection.
There is no such thing as maintaining this solution — everything is baked into it. Unless of course, you want to pay for the enterprise tier. Then maybe you could gain access to extra DDoS Protection.