We're currently using Island Construction for major dock repairs (Once every 60 years level, remove concrete docks and replace.) Last year, they did some major structural work on the camp. Very versatile group. They also do open/close, electrical and plumbing. We're pleased with their work. Point is, we looked for somebody to do the types of work we need, rather than looking for a barge. Most companies that do major island projects have their own solutions for different types of work.
Island Construction
209 Stage Rd
Sanbornton, NH 03269 US
603-387-4992
Island_construction@icloud.com