http://www.findproxy.com is free
http://www.insecure.org/nmap/ then run namp -p 80,1080,8080 192.* is also free
why should I use your services?
Does your scanner find better proxyes that my namp installation?
Do the proxy owners know theyr boxes are used with not very clean purposes?
Tell me why should I pay you $200 per week. I am interested only is your proxies are legit and the owner knows his box will be used by me.