Earlier quoted context omitted.
Bandwidth into both B2 and DigitalOcean is free, bandwidth OUT of them is metered (or in the case of DO you get a bucket of bandwidth to start and then it's metered past that bucket).
Also there appears to be no way in the dashboard of DO to see bandwidth usage. I don't know where they say it's metered after that, because they just slowed down the speed severely when my server went over, rendering it useless for its purpose without warning.
digital ocean charges $0.02/gb after your vm quota is used up.
fyi, amazon/google charges above $0.10/gb