If you want to minimize your cost on private proxies, grab this software. Experiment with the settings and add-ons, make sure your VPS is fast enough that you can scrape at least 1k per hour. I am using this for my GSA SER as an experiment, and I am receiving far more speed than 10 shared proxies.
Note:
- experiment with your settings
- grab another VPS for PM, 1GB will do (always look for coupon codes)
- grab those add ons, they do help a lot!
- look for more proxy listing sites (scrape with gscraper)
- share your proxy in dropbox, other peeps can steal your proxy via FTP (duh!)
- learn how to optimize your settings, look for ways to achieve better results
Cost
1 VPS for GSA SER ($7 with coupon code)
1 VPS for PM ($5 with coupon code)
*don't ask me about the VPS providers, there's a lot in here. Ask for discount
So far I am having success with this kind of set up, I am already optimizing it for the better. Looking to scrape 2k / hr elite proxies

If you're looking to minimize your cost, start here and grab this software. This is a must-have in the long run for SEO tools.