The link below features a proa being built (instead of a trimaran). The techniques and materials, however, may be of interest to many DIY small tri builders as they see how others build outrigger boats.
It may also provide some food for thought on boatbuilding in financially poor areas. This Instructables article is a good follow up to the previous one just posted.
Please note the link is just one page that are part of a series, which are referenced at the bottom: https://www.instructables.com/Aka/