'You never knew when she was going to snap at you'
VP's office described as 'place where people feel treated like s—t'
Boston's Marty Walsh has paid Anita Dunn's firm $90k since September
Previously cited Chairman Mao as her 'favorite political philosopher'
Firm handling coronavirus contract has received $2.1 million from Biden since 2019
Anita Dunn one of more than 75 Democratic strategists to speak with Halperin