What to include in your first message

Car you're considering
Year, make, model, trim — or "still searching" if you haven't found one yet.
Budget
Total out-the-door budget, not just monthly payment.
Location
Where you're shopping — city/state or general area.
Timeline
Are you buying this week, this month, or just researching?
What matters most
Reliability, fun to drive, low cost to own, resale value — what's the priority?
Any deal-breakers
Things you absolutely don't want — mileage, color, transmission, whatever.