Some of these are considerable and some are negligible, but unless you buy one of those DIY spray foam insulation kits, the largest by far is the cost of labor. Depending on your market ...
Foam guns contain more parts than cannons, such as a spray nozzle with trigger and control knob near it that can adjust bead size (1/8 to 3 inches). Furthermore, two-finger triggers make operation ...
There are much cheaper alternatives too, such as the more traditional roll insulation, available for a few hundred pounds from most DIY stores. As for Sandra she's just happy her spray foam is ...