There is of course no point in booking a car rental in Rimini if you intend to spend all your time relaxing on the beach. However, most tourists prefer to actively explore not only the city but also its surroundings and some take the opportunity to visit other famous tourist centres in Italy nearby (San Marino, Venice, Florence, Verona, etc.). In that case, a cheap car rental in Rimini would be a sensible solution, especially for family travellers.
Don't assume that by turning to local car rental companies, you will secure a cheap car rental in Rimini. Although there is an abundance of local companies here, the large firms keep their prices quite high and the smaller ones cannot boast of the quality of service. This is why most experienced travellers recommend renting a car from well-known car rental companies such as Avis, Eropcar, Herz etc. In this case, the price of car rental in Rimini usually starts from 25-30 EUR for a day of renting a mini or economy car (without insurance and gasoline costs).
You'll need a driving licence and a credit card to rent a car and a deposit will be deducted. It is not customary to rent a car in Rimini without a deposit.
There are both free and paid car parks in the city, but during the high tourist season it is difficult to find free spaces. Car parks also have restrictions on parking time, e.g. your car cannot stay in the same spot for more than two days. Parking costs EUR 1-3 per hour.