Hi Debbie, while I am no expert. Here are my suggestions:
What if you targeted the businesses in your area...say starting with the car dealerships (because they are normally lumped together) and take a flyer or business card with you; offer them a complementary cleaning and then have them rate you.
This will do a couple of things:
1. It will give them the opportunity to "love your services". Maybe extra compliments about the cleanliness of the restrooms will be a constant reminder as to why they should choose your service over the one that they have.
2. Having them rate your service will tell you what to do better for them or to impress the next client.
Also, if you land the contract, you will have a reference point for their likes and dislikes and help you get off to an excellent start with your clients.