Make the appointment with anticipated time. This way you will not have to pay more for a rush service.
Make the contract for one year of services. If you make an agreement for 3 to 5 services in a year, you will receive a better price. Always.
Use a company that doesn't outsource the service. It's simple, just ask the business if they will outsource, and also you can check this on the first service they make in your building.
Ask for a better price. You don't lose anything and can save some money just asking a discount
Use other services from the since company. The cleaning services companies usually have more options for new services, ASK them, and use one company for several of your needs, this way you will get a better price every time