Plovdiv starts an inland route. Check the rental appointment against the actual flight timetable rather than assuming daily desk staffing.
The airport lists car-rental providers on its official access page. Agree the collection meeting point, flight details and return procedure directly with the supplier before travel.
A car is useful for linking inland towns, rural accommodation and coastal stops. Sofia-only visits can work without one. For a Black Sea holiday, choose the airport near your base rather than driving across the country immediately after arrival.
Compare airport collection with a later collection if you start with a city stay. Include the transport to a different rental branch and any extra parking nights when comparing the total cost.