we've started using the hotwire system, more of a built it yourself idea, and I'm lost for where i can get coatings for the foam, and for interior use. All i know of are people do exterior, and we're looking into the interior and the only place i've found who sell the mix for the coating will only sell it to us if we buy their machine aswell. Selling for $28,000.. there's only about $5,000 worth or material in it.. so i'm on the hunt for anyone who has any ideas or knows of where i can find coatings for this. Thanks alot for any help.