Kitsune to Sensha to Ougon to

The fox-girl Foxy was feeling down because her troop was still in debt despite fighting as mercenaries. Now Foxy and her friends are traveling in a tank, hoping to earn money through trading, and searching for a legendary plate of great value. Along the way, they happen to rescue a kidnapped girl, Leona, and learn that she has information about the plate and is a skilled trader, too. Foxy is invited to join Leona's caravan as a reward for her rescue. Suddenly, however, the caravan is attacked by mercenaries and destroyed. Burning with vengeance, Leona decides defeat her enemies through economics, instead of taking on their greater military strength. As a tense trading battle unfolds on the commodity exchange, Foxy and his friends, who are on separate missions, have obtained important information that could move the market...

(Source: MF Bunko, translated)