Robbie Veath brings together buyers and sellers of used heavy construction equipment, and helps them negotiate the terms of the sale. However, Robbie never actually takes title to any of the equipment himself, nor does he provide any financing for the buyer. Robbie is acting as a:

logistics specialist.
channel captain.
wholesaler.
broker.

Broker

Explanation:

  According to the given question, the Robbie is acting as the broker that helps in negotiating the different types of products on the basis of different types of conditions.

A broker is on of the type of marketing intermediate which is basically brings together both the producer and the buyers that basically offers the credit and also assume the different types of risk.

The main role of the broker is to manage the deal and transaction between the sellers and also effectively manage the various types of investment related plans.

 Therefore, Broker is the correct answer.