Scraping for posting

Are we able to scrape & use the proxies anonymously - for example, if i get a complaint using a public ip they might give the ip of my vps. 

Can I scrape public proxies for sending using paid proxies?

Or should I use something like Surf Shark in the background on the vps?

You can define what proxies to accept so you can only accept fully anonymous proxies and then no abuse complain will go through.

Learn how to use Proxy Chains