Moving target - Elizabeth Moon

Ky Vatta was a military cadet destined for great things, until an act of kindness incurred her Academy's wrath and ended her career.

Instead of the expected disgrace, her rich trader family gave her captaincy of a small ship, to sell for scrap. In flagrant disregard of orders, she saw the opportunity to make a profit and save the ship.

Several upgrades later, Ky is determined to retain the ship and her independence in the cut-throat world of interplanetary trading. But a threat emerges that challenges even her sharp wits and, if she survives, could leave the military forever in her debt . . .

'An action-packed read, complete with zero-g combat sequences, exploding ship mines, stratagems, and intrigue . . . Definitely recommended' The Book Smugglers