It is easy to open a bank account in Bolivia. You do need to have a Carnet de Identidad (See ) and a copy of your passport, as well as proof of your address. So this means you at least need to have a residency Visa. It normally takes about an hour.
We use Banco Nacional de Bolivia (BNB) but it will all depend on your personal preference. They have both accounts and ATMs for USD and Bolivianos.
Once you have an account I don't think getting a loan would be a problem and long as you can provide security in Bolivia.
all bank loans are at 18 percent interest for ten year max. most loans are for five years. that should stop you cold and persuade you to consider other options before you concern yourself with formalities.