When we started Chimpy in 2014 (power bank rental company in Switzerland, later more EU countries) we got suitcases and hauled the charged power banks to the convenience stores and hauled back the returned ones. Not using cars, but using trains and buses. This was not efficient nor fun, but doing this got us through the pilot phase successfully until we had enough volume to work with a proper logistics company to do this for us. It also allowed us to speak to the people working at the stores and get direct feedback.