Trading in Danger (Vatta's War Book 1) by Elizabeth Moon is currently $1.99 in the US
https://www.amazon.com/Trading-Dange.../dp/B000FBJBA4
https://www.kobo.com/us/en/ebook/trading-in-danger-1
Ky Vatta is a highly promising military cadet with a great future ahead of her, until an apparently insignificant act of kindness makes her the focus of the Academy's wrath. She is forced to resign, her dreams shattered.For the child of a rich trading family, this should mean disgrace on a grand scale. And yet, to her surprise, Ky is offered the captaincy of a ship headed for scrap with its final cargo.Her orders are absolutely clear, but Ky quickly sees potential profit in altering the parameters of the journey. Because, whatever the risks, it's in her blood to trade - even if the currency is extreme danger.