A hundred leads spread across four counties will damage your margin. Twenty inside one ZIP cluster will build it.
Most cleaning contractors ask for more leads. The ones that grow profitably ask for tighter leads.
The Margin Math
Every additional mile between two accounts is unbilled labour, fuel and supervision. A crew that services four buildings within two miles of each other is a different business from a crew servicing four buildings across thirty miles, even at identical contract values.
What This Means For Targeting
Choose ZIP codes the way you would plan a route, not the way you would draw a sales territory. Start where you already have accounts, saturate that cluster, and only then expand outward.
The Practical Test
Before adding a ZIP code to your target list, ask whether a supervisor could reasonably cover it in the same shift as your existing work. If the answer is no, it belongs in phase two.