Internet Search/Scraper for Classifieds

Hello, we buy and sell early Porsches and need a program that can search the internet and all classifieds (Craigslist, backpage, etc.,NOT EBAY) and email us immediately when a new listing is created. We have a list of keyword phrases we can supply. We would also like the ability to add and remove keywords if necessary. The search must happen continuously through day and night, and must email us directly when a a result is found. We can install on our server if necessary. In our business it is important to be the first person to respond to these ads. Attached is a preliminary list of keywords. Thanks, -Mike