Over the past several years, youth hostels have sprung up like tango halls in Gardel’s time, and most of them are good to excellent at modest prices. Some but not all are Hostelling International affiliates.
It actually lies within Retiro [1], but HI affiliate Recoleta Youth Hostel (Libertad 1216, tel. 011/4812-4419, www.trhostel.com.ar [2], US$10–12 pp dorm, US$39–50 d with private bath) still boasts an excellent location—arguably the most prestigious address of any hostel in the city. Rates are higher on weekends.
Congreso’s St. Nicholas Youth Hostel (Bartolomé Mitre 1691, tel. 011/4373-5920, www.snhostel.com [3], US$10 pp dorm, US$41–46 s or d in private rooms) is another rehab with ample common spaces; those common spaces, though, are so close to the dorms that it can be hard to get to sleep at an early hour.
Near the Facultad de Medicina, Hotel del Prado (Paraguay 2385, tel. 011/4961-1192, www.hoteldelprado [4] ba.com.ar, US$25 s or d) is a plain but tastefully remodeled older building with a quiet interior, good beds, and friendly owner-operators. Rooms have private bath, cable TV, telephone, and ceiling fans but no air-conditioning; there are discounts for extended stays.
Links:
[1] http://www.moon.com/destinations/argentina/buenos-aires/sights/retiro
[2] http://www.trhostel.com.ar
[3] http://www.snhostel.com
[4] http://www.hoteldelprado