I read this book end somewhere between 1999-2006.
I think it was part of a series. I believe I read 2 or 3. I believe it was labelled as a young adult book. I think it had some sex in it but my memory is hazy.
It's about a female who pilots a Cargo/Transport spaceship. (I believe her name started with a K or possibly the authors name started with a K.)
She transports cargo to different planets or ships to make money. (The currency might have been referred to as Credits, not sure though)
I think there was some sort of body modification in it. (For example, someone could modify themselves to feel more pleasure or feel no pain. I can't remember but they may also have been able to have chips installed for telecommunication. There may also have been people with android parts but I'm hazy on that part.)
I believe the cover had the main character on it with a ship in the background but I can't remember.
Every few years it pops into my head but it's so vague that I can't seem to find it when I search Google.
I think you can classify it as an Action-Adventure with some undertones of Romance.