The script will give the user a random file name. User will be told he/she needs to upload a text file with that file name to the top level of their site, example:
[url removed, login to view]
Once they have done so, they will click button on script, and script will then go try to access their site, looking for that filename.
If file is found, success. It file is not found, deny.
Doesnt have to be pretty, im going to fit it into another project im working on. The purpose of doing the above, is so we can guarantee that the user, is the actual owner of the site they will be submitting to us.
Best of luck on the bidding!