Spanis learning programm - open to bidding

We have a PHP project for learning Spanish and there are certain requirements we need help with. The requirements are the following: Give students Foreras for each correct answer 1. First unit it’s free. The rest of the units will be blocked unless paid 2. Give the option to print gramatical points (the buttons is already there, verify if it works) 3. Chat between students and teacher 4. When in a gramatical lesson, give possibility to open a window with related exercises to practice 5. Automatically present the results at the end of each exam 6. Allow teachers to create their own exams by combining questions and exercises from each lesson. E.g. if they click on an topic, they can choose how many questions from that topic to include in their exam. In the end they can see the complete exam, choose how much time students will have to solve it and send it to them. Would you please inform us about the time it would require you to finish it and the cost? Thank you in advance