I want a translators marketplace website

I want a translators marketplace website with same functions of onehourtranslation.com, but I also want another function. That website only support instant translation (a client posts a translation projects, the system sends notification emails to all certified translators of the language pairs specfied by the client, the first translator who click "take this project" will get the project and starts working immediately, because Once a translator starts working on the translation a countdown timer shows when the translation is going to be ready. Translation of one 200 words page normally takes less than an hour. The system will send an email to remind the translator when there is only 10% time left. The translator must finish and upload the translation before time out. I need all its functions, but I also want "project bid" mode, that's to say when a client post a translation project, he can select "instant translation" or "get bids". If he select "instant translation", the process is the same as onehourtranslation, if he select "get bids for my translation project", the process is some like peopleperhour. Please note that we only want the site be built with PHP+MYSQL. Thanks