The system allows the operator to determine the percentage of the rewards obtained for producing blocks to pay for the stake pool maintenance costs (hosting, internet connection, etc.).
The system pays that amount to the operator once the stake pool produces blocks. The operator is paid first and the rest of the rewards are distributed (by the system, not by the operator) among the delegators.
The 500 ada is returned once the stake pool is retired.
The operator does not have to pay the system anything if the stake pool does not produce blocks.
Do you remember the first point? Well, the minimum amount that the operator can set as payment for his work in maintaining the stake pool is 340 ada.
Thank you for posting this question tokyo! I am in the same boat!
napoles i appretiate the replys! Helped alot. I just wonder someone with little ada under 1k how could i really make a pool and get it producing blocks for the system. The lowest producers have like 100k minimum dont they?