This is an external airport gateway: Rimini Federico Fellini Airport (Italy, gateway to San Marino) is in Italy, not San Marino. The rental contract must permit the onward international journey and every transit country.
RMI is in Italy. Compare a rental for a wider regional stay with a bus or transfer for a short San Marino visit, and obtain explicit permission to take the car into San Marino.
The airport’s passenger information identifies an on-airport rental operator. Follow the selected supplier’s voucher for its current office and return area, and confirm flight-linked handover. An airport listing does not guarantee availability, opening hours or cross-border permission for every offer.
A rental can be useful when San Marino is part of an Italian regional journey or when staying outside the historic centre. For a short visit from Rimini, compare buses or transfers and walking. The main sightseeing area is a place to park and explore on foot rather than drive between every attraction.
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.