Add Paypal withdrawal function, multi-file upload and a simple search function for an existing website

An existing website needs the following ; You can see the website from here : [login to view URL] The website provides a note sharing platfrom where users upload notes, set a price other users buy them. Most of the following functionalities are partially done : 1- Paypal function : Users should be able to withdraw money with a minimum of 10 dollars. If they withdraw any amount less than 10 dollars they should be charged a fixed fee of 0.75 dollar. Also for Deposit there has to be a limit of 5 dollars. Right now users can only deposit. 2- A simple search function based on keywords . Right now there is search function that only searches through note titles. I want this to be extended to keywords (for example when a user uploads a note with title "Algebra" in University of "Texas" in Course "X" I want other users to be able to type "X" and see a list of all notes that have keywords "X" in them. 3- Multi-file Upload, right now users can upload one file at a time, I want them to be able to add multiple files at the same time. Also I might need to make some minor changes to the project description as we go through it. If I want something else that is a major change you will be compensated. Also my budget for this is $300.