My new taman in Penang, there is a group of guards from a local company asking for monthly fee (like asking protection fee) for service to ronda our taman from night to morning.

While they said it is up to us want to get their service or not, I afraid that if we didn't give them, they will "do somethings" on our house or our car when we are not around.
I noticed that half of the residents here gave them while another half not.

My question, how can i know is this so called guards legally appointed to guard our taman, or is it any guards service company can simply come to any residential area to provide their service?

Not that i don't want to give them, but I don't see they doing their job much. Most of the time, I can't even see them at night.
Just occasionally riding  their motorcycle and go around the taman to check fora while, then disappeared.

I rather give more $$ to those proper guards that really setup a booth in front of the taman entrance and gated all the surroundings.