In a small economy where individuals specialize in trades, they may find the process of setting up a centralized currency and maintaining it an unnecessary burden in order to trade. One option may be to use a commodity to exchange value between parties that want to trade goods or services and this is why gold and silver have been useful forms of currency in many cultures and times. Another option may be to use a barter system to trade.
While it may be free, there is no one monitoring the barter ads, so you must be aware of potential Craigslist scams, and realize that you are always at risk when it comes to meetups and exchanges. For example, about a year ago, I arranged to trade massage gift certificates for housecleaning. Since the individual was coming to my home, I was more nervous than usual. However, she offered good previous references, and we  arranged for a time to meet when my husband would be home, in case an odd, unexpected, or even dangerous situation arose.
The troubles that the people of Venezuela are going through are horrible and in all reality, really shouldn’t be happening.  Venezuela has a tropical climate and is an oil producing country. They should at least be growing their own food in the countryside.  This would help those who are starving.  But those in power, the elite, don’t care about the common people and make it hard on them at every turn.  While the elites have access to the food, medicine and all the power they want from their electric grid, the common people have had to make due with what they can scrounge.