one of His Majesty's bad bargains

as best one can

In the best possible way, given one's circumstances and abilities.

as far as one knows

To the best of one's knowledge, as far as someone knows or possible information to be gathered about the topic, subject, aspect, or situation.

back to square one

Located back at the start, as after a dead end or failure.

bad actor

An individual or entity with a prior criminal conviction, or who has been sanctioned by the court or regulator.

bad apple

A person who is not wholesome, honest, or trustworthy, especially one who has an adverse influence on others.

bad books

Disfavor.

bad business

Synonym of bad news (“irritating, troublesome or harmful thing, situation or person”).

bad company

The wrong crowd.