Not a tour operator: the overnight bus between La Paz and Uyuni, and the one most people take to get there. Forty-nine dollars for a cama ejecutivo — a seat that lies flat — or forty-four for the semicama, one way, booked online with a seat number rather than by turning up at the terminal.
Worth listing because the Uyuni trip is a logistics problem before it is anything else: the bus leaves La Paz in the evening and arrives in time for the morning departure onto the flat, which is the whole reason the tours start when they do. They will move your booking up to 24 hours before departure for five dollars.
Two mobiles, both on WhatsApp. Note their own terms warn about road blockades — a routine feature of Bolivian travel that most operators do not mention.
They publish no street address, so the pin here is the town centre.