The combination of: a) a wheeled operating unit having a drive powered by a rechargeable power supply and at least one connector; and b) a charging station having at least one connector. The at least one connector on the wheeled operating unit and the at least one connector on the charging station cooperate with each other to establish an operative connection between the charging station and the wheeled operating unit, whereupon the charging station is operable to effect charging of the rechargeable power supply. The operative connection can be established with the wheeled operating unit moved selectively from first and second different starting positions, each spaced fully from the charging station, respectively in first and second different path portions up to the charging station and into at least one charging position.