Hostels in Bolivia are some of the cheapest in the World. The average backpacker hostel runs between $2.50 and $3, for a clean private room with shared bath with cold water. In the Altiplano, cold water isn’t exactly comfortable but for an extra $1 it is usually possible to get your own bath with an electric showerhead that will shock you if you come near it. In the major tourist areas there are always backpacker hostels. A good bet is look for where the Israelis are, as those are likely to be the best value on the low end.
In major cities there are also mid and occasionally high range accommodation, however, as big tourist groups are rare in Bolivia it would be very rare to see a 4 star hotel. For $10 a traveller should expect a very nice and comfortable room with good hot water and a TV. At the $20 level, some luxury should be expected.
In the remote areas, it can be possible to stay with the campesinos or tribesmen, though it is always wise to take a tent if possible. Wood is virtually non-existent in the Altiplano, so take a stove with you if you need to cook. Remember, supplies like camping gas and white gas are very limited, so you should bring it with you from another country.