The following applies to us.
For rainwater, also called precipitation water, which is collected from roofs, driveways, etc. in a cistern and then used for garden irrigation or infiltrated directly on the property, no precipitation fees need to be paid.
I had to check online because we have not paid precipitation fees for several years.
Here, 1.36 euros per m² of sealed surface per year must be paid.
If the cistern is connected to the sewer, half the amount must be paid for each m².
And as mentioned, if the cistern is not connected to the sewer but ensures that the rainwater only infiltrates on the property itself, nothing is paid.
A meter is also not necessary.
If you want to use the rainwater inside the house, a meter must be installed so that the rainwater, which then becomes protection water, can also be billed.
I myself very much regret that I was only able to bury a 4 m³ cistern.
If possible, get a large cistern.