Taxis are very cheap,is about 5 USD each 4 kilometers year 2010 take into account that Argentina has +/- 15% annual inflation , prices change in ARS but remain the same in USD. Cabs drivers are plentiful, and pretty honest.There is a local bus network very large , you need a bus card in order to use it, it can be bought in terminal bus or in bus office usually in downtown and reloaded in drugstores.Another transportation service is Remisse , is like a cab with a discount , you have to call "the remiseria" , a sort of small terminal with a operator at phone. Almost for sure , no one speaks english , so be ready to make signs or talk in spanish with the drivers. If you want to walk, Mar del Plata is perfect , it has 28 kilometres of coast with lights and pavement and is pretty safe.
