Market stall manager for Charity

Hi, Im using my skills to provide a stall manager system for a charity i volunteer for,. I will be paying with my own money as a donation and my time too! please keep this in mind,. also this project can take a 4-6 weeks to you can do other work in between to keep the fee down. Job: I have very good sql, php knowlede and how it all works (not good at creating from scratch though) so i will help with lots and also make the info simple and easy to follow to minimise your time trying to work things out. The aim of this is the charity i volunteer for runs weekly markets, they currently use scraps of paper to manage over 100 stalls and the poor old ladies struggle, so i want to create an online system for them. This will be a Stall holder area, they sign up, apply for markets etc. Admin area: setup events and markets, assign stall holders to numbers (i might get some other developer to create and interactive map for this) and history of stall holders etc. I will provide a detailed list and also setup ftp and sql on my paid server. Again please be helpful with the price! thank you