ManageCasa offers a free subscription plan as well as a paid PRO subscription.
In the case that you want to cancel your PRO subscription, you need to go to Subscription under Settings and lower the amount of properties you're managing to three or fewer.
At this point, you can select the FREE plan.
You will be prompted in a pop-up to finish cancellation with some further explanation about when your paid subscription will be terminated. Also read this article to determine when your last charge will occur.
If you still have more than three active properties, you won't be able to downgrade from the PRO plan until you remove all properties except three from your account.
Please don't hesitate to contact us if you have any further questions.