Some embodiments provide a system comprising: multiple self-propelled motorized transport units; a wireless communication network; and a central computer comprising: a transceiver, a control circuit and a memory storing computer instructions that when executed by the control circuit cause the control circuit to: receive a request from a customer requesting location information for a requested item; identify the requested item is a category of items, and identify category location information; communicate routing instructions to the motorized transport unit based on the category location information causing the motorized transport unit to initiate physical movement; and communicate to the motorized transport unit a species clarification inquiry instruction configured to cause the motorized transport unit, while implementing routing instructions to move toward the category location, to present a clarification inquiry to the customer seeking clarification in narrowing the identified category to one or more products categorized within the identified category.