The pedestrian zone, and what it means for pickup
The core of Baščaršija is pedestrianised. Most apartments in Sarači and Kazandžiluk cannot be reached by car, whatever the listing says. That is not a problem, but it is worth knowing in advance.
In practice we hand the car over at the nearest point a car is allowed, usually on Obala Kulina bana or by the City Hall, leaving you a few minutes on foot. We agree the exact spot by message, with a pin, so you are not circling and searching.
The car is for leaving the city, not for the city
Everything you came to see in the old town is walkable: the Sebilj, the Gazi Husrev-bey Mosque, Ferhadija, the Latin Bridge, the City Hall. Driving between them would make no sense even where it were allowed.
So people staying in Baščaršija take a car for what walking cannot reach: Vrelo Bosne, Bjelašnica, Jahorina, Mostar. If you only need it for one such day, say so, because a short hire is calculated differently.
Narrow streets and the climb to Vratnik
The streets above the bazaar, up towards Vratnik and Bistrik, are narrow, steep and often one-way. If your accommodation is up there, a big car is a genuine burden rather than a question of comfort.
For that part of town we suggest something small, the Mercedes-Benz B-Klasa or the VW Golf Sportsvan. If you still need a bigger vehicle for the travelling, tell us where you are staying and we will work out whether the approach is realistic.