PHP Programmer/Web Developer

I have an open-source web app that I need customised to suit a client's business. My client has a dog training business and needs a management app to suit 3 different training centres with an overview dashboard for ADMIN. This app needs to be able to handle the booking in process, time-management for several different trainers and financial reporting and invoicing. The guts of the processes can already be handled by the app I have chosen (Ultimate Contact Manager) but I need a proficient web developer that is able to complete the task based on the client spec. I need this done ASAP and this should be viewed as a test(PAID) project to see if we're a suitable fit for one another. The successful candidate will have an opportunity to join my team and work on many similar web development and SEO programs.