The first few chapters show a problem common to new writers; their characters all sound the same. A kid would naturally use less complex words than an adult. Someone trying to intimidate sounds the same as the one they're intimidating.
Another is the use of dialog as exposition. Of course you have to have exposition in the story, but they should be written as if the dialog is being said by an actual person for an actual purpose and not just obviously for exposition. A way to migitate this is to break down large exposition dialog into readable chunks, sprinkling in descriptions of what is happening in the scene.
For instance, this chunk of dialog taken word for word from the chapter:
"Heh, you're sharp. Sorry about this, jobs a job. You're right though. We're not Econican soldiers. We're a group called 'Checkmate'. We were hired by a group of Orthlys nobles who'd benefit from a war. < I removed some dialog here to shorten the example >" He said as he took a cigarette out and lit it.
And compare it to something like this:
"Heh, you're sharp.", chuckled the boy, his child-like voice in odds with the situation. "Sorry 'bout this, but jobs a job.", he shrugs dismissively.
"But you're right though, we're not Econian soldiers. We ", at this he waves his arm towards his men, all much taller than him, gesturing flamboyantly, "are 'Checkmate'. A bunch of strapping young lads hired by some Orthys nobles to cause some trouble. Heck maybe even start a war or two for their benefit.", the boy drawls, taking out a cigarette from one of his pockets and taking a lazy puff.
With this description, the reader can fill in the rest of the scene. How the boy stands, perhaps mockingly, facing the main characters. How his men are just standing behind him. Maybe they are at attention, obedently waiting for orders, maybe they're standing in a loose, unorganized sprawl. Are the men eager for battle, with grins on their faces as if the main characters are the only things separating them from a large payday?
As the first few chapters are right now, I will not read any further. However the writing basics, like spelling, grammar, etc, are quite fine. Which is why I'm rating this as above average, not bad for a first time writer.