How it used to be done
My experience has largely UK Military and police flying, I did for a period fly corporate out of a small London airfield. The company I worked for held an AOC though we were based side by side with many other aviation enterprises and shared the airfield cafe with the whole spectrum of pilot's and visitors/clients etc.
The basis of our businesses was to offer a corporate service of providing aircraft and crew for charters, most business would come via a broker, these brokers would receive a request from a client and then phone around the companies to find the best fit and lowest cost. It often became a back and forth negotiation with our ops staff. We pilot's would be allocated the task the day before unless it was a rush job.
The client would often have no idea who or what would be flying them until they arrived at the agreed pick up point. They certainly would have no idea of the pilots qualifications or the capabilities of the pilot or the aircraft.
It often turned out that the broker had promised things to the client to seal the deal that left we pilot's spinning plates on the day, or having to explain the real world to the client in an uncomfortable conversation.
It was also the case that one pilot willing to bend the rules or give in to the client could set a dangerous precedent for those that followed.
In summary, I'd be looking at the broker first and foremost and work out in both directions from there.