Reduce WLAN Bandwidth for a public Hotspot

[hobbyist]

Hi, i plan to build a public Hotspot, due to data volume limitation of the underlying connection, i m looking for a solution to reduce the bandwidht of the Hotspot to avoid that a single user can use the full Data volume in a very short time.

I have two different ideas how to do that. Limit the bandwidth of the Wlan, or limit the data volume for every single MAC id.

Any idea how to implement this?

Thanks in advance

hobbyist