No need.
A client can be on a free plan forever, I have nothing against it.
The free plan has limitations, which are openly written on the site -
https://crm-onebox.com/ru/prices/1. you can not participate in the free improvements program;
2. limitation on allocated resources;
3. The box is automatically backed up and deleted after 7 days if no one has logged into it. When you enter, a page like
https://crm-onebox.com/ru/onebox-deleted/?box=mm555.crm-onebox.com will be shown
You can restore it in 1-10 minutes and again it will be 7 days.
In the future there will be new restrictions, but it will look like this: we will make a new application, but it only works with paid plans.