Argentina offers a wide range of accommodations, from luxury hotels to more affordable lodging. In large cities like Buenos Aires, Rosario and Córdoba, there is presence of large international hotel chains such as Radisson, Hilton, etc. Depending on the season, these places can be seen crowded with tourists, so it is always wise to make your reservation in advance and for this, the internet offers many good resources.
On the beaches of Argentina is also quite common for houses to be rented fortnightly or monthly. This is typically what the Argentinian folks do in the months of January and February, so if you have a long vacation you can also explore this option.