Double-Blind

Double-Blind - Loren L. Coleman, Loren Copeland Avanti's Angels, a mercenary unit, are sent out to the Periphery to investigate why raiders from the Marian Hegemony against the Magistracy of Canopus are so well equipped.

Throw Comstar/Word of Blake and Sun Tzu Liao into the mix and you know deception will be involved.

The Angels are a good unit, not infallible and worrying about how to keep their equipment paid for.
Most of the action takes place on a desert planet, with various rulers trying to influence them, and the fighting is quite intense.