The 10% fee is all that is required, the only time you would need to put up collateral is if you do not avail yourself of a bail bondsman, when a bail bondsman post bail they assume responsibility for the person and have Bounty hunters who enforce compliance.~
Of course you have to put up collatoral. If your brother does not show up to court the bondsman has to fork out 20k - then the bondsman is going to go after whoever posted bail… how are they going to get their money back if you have no collatoral?