Continuous edits on existing complex web site

I am looking for a programmer to update my custom web site. Must understand data bases, csv files, and pay pal integration. This is a complex site and i need someone who can respond at the longest of one day. Must be able to follow a list of requests and testing of the site before uploading. If you are new to programming this is not the job for you, I have continuous work and need someone dedicated and responsible that can work on their own without supervision.