In Bolivia and in particular, transit offer to use their own AS via their own IPv4 block (even worse for IPv6) is near impossible. It's the reason for low use of AS in Bolivia.
Most of the user/ and company have access to network access, sometime with static public ip.
To lower cost, most of small ISP reuse the network access to anunciate their AS out of Bolivia via tunnel/VPN. The IXP is not well developped into Bolivia, mean part of communicate is done out of Bolivia.
Each small AS can connect via tunnel/VPN via common ISP. This don't need any autorisation of any ISP, you gain time, cost and it's very less complex. Each big AS can use IXP, each IXP should connected via most common ISP.