According to the web page https://www.digitalocean.com/docs/billing/bandwidth/, droplets include free outbound data transfer, and excess outbound data transfer costs $0.01/GiB.
This price is not expensive. However, it makes it possible for the cost to rise unlimitedly. For example, if there is some DDoS attack against my droplets, then the outbound data transfer may rise unlimitedly, and consequently the cost may rise unlimitedly.
I hear that there is some billing alert feature, which can send me an e-mail or something else to alert me when the monthly cost exceeds a limit. But this is not enough, because I do not want to keep monitoring my droplets all the time. If a huge DDoS attack against my droplets happens when I am sleeping at night, then the alert will not help me much.
So, in order to prevent the outbound data transfer from rising unlimitedly, I want to be able to set data transfer limits on my droplets. In detail, I want to be able to set a monthly outbound data transfer limit on any droplet. If this limit is reached, then this droplet will become unable to send data in this month. Also, since this droplet cannot send data in this month, it makes no sense for it to continue receiving data. So, this droplet should also become unable to receive data in this month. Of course, I should be able to change this limit at any time, so that if I want, I can allow the droplet to continue sending and receiving data.
I don't find this feature in DigitalOcean. So, could you please add this feature?