I work for a homeless shelter. Our kitchens are inspected by both DHEC and Veterans Affairs (we house veterans so the VA gets involved). Despite being a homeless shelter, we have one of the cleanest commercial kitchens around and still pump out roughly 500 meals a day.
We have one operation that uses our stuff and it doesn't cost her much. I think her deal was basically a few donations of food and whatever else. She comes in after we serve lunch so it's rather dead. We get people all the time wanting use our kitchens but need a full day or two. That just can't be done.
But if you have a place like that around you, that isn't sketchy, is clean and has a schedule you can work around, it might be possible to get it cheap.
In South Carolina, any facility that serves the public must be DHEC inspected. I'm certain most health departments have similar requirements. Churches here get a pass because they don't technically serve the public but rather their parish or whatever you call them. Even two of my kitchens get a pass because we only serve the public out of just one and the other two are used only for residents.
If you have a food truck contingent in your area, ask them if they use a commissary type kitchen somewhere. That could be another resource.