La Merced [1] is a rather unappealing town, and its lodging options are lackluster. San Ramón [1] is cleaner but has few services. If at all possible, spring for the charming bungalows between the two towns.
La Merced has a few plain but clean budget hostels—the trick is avoiding street noise.
Hospedaje Cristina (Tarma 582, tel. 064/53-1276, US$9 s, US$13 d) has parquet floors and peeling walls but the bathrooms are clean. It also has cable TV.
In La Merced, Hostal El Rey (Junín 103, tel. 064/53-1185, US$21 s, US$29 d) has been in business 30 years and has excellent service. It has retiled all of its rooms, which have private bathrooms, hot water, and WiFi.
In San Ramón [1], a highly recommended option is the peaceful, quiet, and friendly Hospedaje El Parral (Uriarte 355, tel. 064/33-1128, US$13 s, US$21 d).
Just east of San Ramón, cheap bungalows are to be had at Hospedaje El Rancho (road to waterfall El Tirol, tel. 064/33-1076, elranchoperu [at] yahoo [dot] com, www.geocities.com/elranchoperu [2], US$27 d with breakfast). There are no luxuries here, but the river is nearby and the bungalows are nice and out of earshot from the road.
The oldest, and still the best, bungalow option in Chanchamayo [3] is Hostal Golden Gate (just west of Herrería Bridge outside La Merced, tel. 064/53-1483, US$22 s, US$39 d with breakfast), named after a nearby bridge that resembles the San Francisco bridge in miniature. This place was opened in 1983 by longtime Chanchamayo residents Rodolfo and Divna May. Service is friendly and informal; there are several family bungalows lined with beautiful dark wood, between gardens against the hillside. Other services include table tennis, a bar, a communal barbecue, and swimming pool.
In San Ramón [1], El Refugio (El Ejército 490, tel. 064/33-1082, www.hotelelrefugio.com.pe [4], US$22 s, US$36 d) is a very good choice, with 21 bungalows, gardens, swimming pool, WiFi, and a good restaurant.
Links:
[1] http://www.moon.com/destinations/peru/the-amazon/chanchamayo/san-ramon-and-la-merced
[2] http://www.geocities.com/elranchoperu
[3] http://www.moon.com/destinations/peru/the-amazon/chanchamayo
[4] http://www.hotelelrefugio.com.pe