Auto capture property assignment from website

We need a software that will refresh a website every 30-45 seconds. when a new assignment is posted, then it must instantly decode the captcha code (very simple code - not wavy - just straight upper and lower case letters) and then hit the accept assignment button and return. The assignments are very competitive and they only stay on the screen for a few seconds, so the software must be very robust. it must also have a "maximum number" feature - so if there are 30 assignments that show up at once, we can set the limit at 5 etc.