Same. We put the solar panels on as part of a community buying group project as well in 2016. So far, so good, but now the installer is bankrupt because they grew their business faster than they could handle it. Working on insulation/roof/siding issues to improve the house before switching to heat pump (probably ground-based). Triple pane windows (probably would be better to eliminate half of them instead).

The house was not built for energy efficiency at all. As with most American construction, it was driven by profits of the land speculators and real estate sales, not the future of the place.