The first question on the call is which jurisdiction the house is in
Before budget, before scope, before anything: where is the property.
A firm that works the District and Northern Virginia but not Montgomery County needs to know within twenty seconds whether the caller from Bethesda is a client or a referral. Asking anything else first wastes both people's time.
Put it at the top of the call script and at the top of the web form. Whoever answers should have a one line answer for each jurisdiction you serve and each you do not, plus a name to hand the rest to.
Jurisdiction also sets the rest of the conversation. Permitting paths, historic review and inspection sequencing generally differ across the District, Montgomery County and Arlington, and the questions worth asking change with the answer.
Never state requirements as certainty on a first call. Saying it depends on the jurisdiction and is worth confirming with the local building department protects you and sounds more competent than a confident guess.