You can start and run your own business, working for yourself, fumigating houses for money. You should find out all the applicable laws for your area, as fumigation is a serious business. Lots of homes are fumigated to kill termites, insects, and other pests. Usually if someone buys, or sells a home, it is tented up, which method, you cover the whole complete house with a canvas like material, and make sure no one is inside the home, no pets or humans, before you start to fumigate the house, that is the most important thing.
Usually a home or building it completely covered, and chemicals are set off inside the enclosed ecosystem, just like a big circus tent, and the gases inside are supposed to kill anything inside, including humans and pets, so that is nevertheless the most important part of the job, making sure nobody is inside, when the gases go off.
You could contact pest control companies in your area that do not offer fumigation sets. Offer them, and let them know you would give them a percentage of the invoice, for any jobs they turn your way, and you do.
You should have nice signs on your means saying you are in the fumigation business. When you cover a house up, that is your best place to hang a nice big sign. Other home owners in the area will see the house that is being fumigated for sure, when it is covered up like a great big tent, and a sign there is your best exposure for other customers.