On a Wednesday night in early June, Rene Nezhoda leaned back in a Secretlab gaming chair, fiddled with a computer keyboard, and stared into a camera while looking very much at home. Clad in his company’s black “Bargain Hunters Breaks” T-shirt, Nezhoda carried what could be viewed as an imposing thick-built frame, until he opened his mouth and revealed a self-deprecating charm coated by a soft German accent that would be familiar to fans of A&E’s reality TV franchise Storage Wars—where he and his...