What is the usual fee from real estate agencies in Krakow charged to flat owner

Hi All,
Do you have any idea of what a real estate agency typically would charge an owner for finding a tenant in Krakow ?

60% of a month rent or more? Does it depend on the potential tenant lengh of stay?

Do they charge both the tenant and the owner or just the owner ?

Thanks a lot for the info,

I had to pay 50% of my rent. It was actually pretty cheap because a other agency wanted a full month.

I paid a full month.
So the price of the apt pr. month - charges, that was the commission I paid.
I heard afterwards though that you can easily negotiate this, I just wasn't aware at the time.