If you see an error that states "{Equipment name} is unavailable or incompatible, please change or remove it," there is targeting set up that is restricting it's use on the design.
An org admin can view targeting rules by viewing the equipment settings (Settings > Equipment > Modules/Inverters/Batteries, and then clicking the equipment name), and then clicking the edit icon on a pricing option.
Equipment can be restricted by authorized dealer, city, deal template, equipment, finance method, market, sales team, utility, or zip code.
If your deal does not match all rules set up, you will see an error.