Two counties, two campaigns, two budgets that never borrow from each other
Hillsborough and Pinellas are separate auctions with separate travel realities, and averaging them produces a number that describes neither.
One campaign spanning the bay will drift toward whichever side is cheaper per click. Cheaper clicks are not better patients. If the Pinellas side clears at a lower cost and books people who cancel their second appointment, the account is quietly funding its own churn.
Split at the campaign level so budgets cannot bleed. Separate bid strategies, separate ad copy, separate landing pages, separate call tracking numbers. When you review performance, you are then comparing two markets rather than looking at one blended figure.
The exception is a metro-wide case type. Full-arch or complex surgical work travels in a way that hygiene never will. Give that its own campaign with its own geography, and keep it away from the everyday new-patient budget.
If you only run one location and only serve one county, do not build the second campaign at all. Restraint is cheaper than optimization.