If you're buying transit, you'll have a hard time getting away with less than 10% commit, i.e. you'll have to pay for 10 Gbps of transit to have a 100 Gbps port, which will typically run into 4 digits USD / month. You'll need a few hundred Gbps of network and scrubbing capacity to handle common DDoS attacks using amplification from script kids with a 10 Gbps uplink server that allow spoofing, and probably on the order of 50+ Tbps to handle Aisuru.
If you're just renting servers instead, you have a few options that are effectively closer to a 1% commit, but better have a plan B for when your upstreams drop you if the incoming attack traffic starts disrupting other customers - see Neoprotect having to shut down their service last month.