Hi Wangnei,
I have reviewed your requirement of a building a payment system similar to freelancer.
* Feature of advance deposits in order to ensure security will be integrated along with the ability to create milestones.
There will be a fixed commission for each and every transaction made through your portal.
* Before milestone release, if anything goes wrong, the person can easily ask for dispute.
Once I get your requirement in more detail, I will provide you my complete working plan with precise time and budget estimation.
I assure you will get quality work at the best price and within given time frame. Please drop me a message to discuss this project in more detail.
I would be glad to receive your response.
Regards
Brijesh L