Build the geography municipality by municipality, and let Ladue and Florissant carry different bids
A radius drawn around your office is the wrong shape for a county where a short drive crosses a dozen separate municipalities with different housing and different owners.
Radius targeting is a convenience for whoever built the account. It is not a description of your business.
Build the geography as an explicit list. The City of St. Louis as its own campaign. St. Louis County as its own, with municipalities grouped by what the properties look like and what they rent for. Clayton and Ladue behave differently from Ballwin and Chesterfield, which behave differently again from Florissant and the north county municipalities.
Group by what you can actually service. A door your maintenance tech cannot reach by mid morning will cost you money regardless of what the click cost.
Set location options to people in your targeted locations rather than people showing interest in them. Otherwise you pay for out of state readers researching the market, and some of those clicks are expensive.