The classic consulting model sells you senior people, then quietly staffs the work with juniors. It looks cheaper. It rarely is.
Senior engineers make fewer expensive mistakes, ask better questions earlier, and leave behind systems the client can actually run. The premium on the rate is dwarfed by the cost of rework, downtime, and technical debt you'd otherwise inherit.
So we keep teams small and senior. The person who scoped your project is the person building it.