Wordpress + PHP Developer

I am myself an eminent wordpress developer and right now I am thinking to recruit someone to my company. I will give several microjobs a month which will add up to 500 USD. Here are some requirements and terms and conditions. Requriements : 1. Please bid exactly '500 USD' otherwise it's a waste of time 2. I will give you a mini task of positioning menu of a wordpress site in a desired position so that I know I am talking to a right guy and it is a 20 in job to a PHP coder. If you fail, no contact. 3. No milestones upfront, you finish a small work, you receive it's money instantly when I am satisfied. 4. If you don't reply within 12 hours of my messages, termination of contract cause it is a common issue in freelancer.com