Projects run with a named delivery lead and a named engineer from first call to launch. You get weekly demos against the plan specification, a shared issue tracker your team can see, and a decision log recording every plan rule and why it was configured the way it was.
Payment follows milestones tied to working software: specification sign off, engine acceptance after the scenario suite passes, integration acceptance, and launch after the parallel run reconciles. If a milestone fails, the next invoice waits until it passes.
After launch the support window covers fixes, monitoring and plan adjustments. From there you either take the handover documentation and run it with your team, or continue on a monthly maintenance retainer that includes a change allowance. Both paths are priced in the open, in the contract, before work starts.