Question regarding proxies

I have been looking for a reliable source of public proxies and in the process I noticed there are a few services that advertise list of proxies that they scrape. I have a few questions and hope someone with experience can shed some light in them.

1. Where do all these proxies come from? Why would anyone deliberately set up a proxy server on their server/machine?

2. How do these scraping services find them?

3. What is your choice of proxy provider/list when it comes to scraping google results?

Thanks!

Not an expert but...

1. Those proxies are most likely not safe and I wouldn't use them for any delicate things like bank account logins or even wp-admin login (any logins). Your thinking is right. Why would they do it? They must be getting some return... I'm pretty sure there are honest ones but...

Can't answer 2. 3. in enough detail sorry.

If you need proxy only occasionally I suggest you check out Epic Browser. It's a free browser that has 3-5 built-in proxies (you can disable it). They change randomly mostly US. Been using it for a while even for more sensitive stuff (PBN logins) and so far no issue.

1. Scraped proxies are usually not set up deliberately, somebody's computer may be affected with malware and become a proxy without his knowledge. The ones that are set up deliberately may be trying to steal your login details, etc. Generally, scraped proxies are not safe and they do not offer quality because everybody is spamming them to death.

2. Many times they can be found by scanning ranges of IPs for open ports. If a machine is affected by some malware and is a proxy, it's published on proxy lists.

3. Residential IPs are the way to go, data center IPs are very easy to ban, even if it's not your fault somebody can abuse your provider's IPs and whole range could be banned.

1. Proxy services are mainly for protect privacy and these days highly used for SEO.

2. Public proxies are spammed to death by many other users since they are freely available for anyone and these free proxies often unreliable and very slow in speed means not recommended generally.

3. Private proxies are the way to go when it's come to Google scraping since they are not used by many users at the same time and will not be blocked while using with proper delay settings (for example with scrapebox) if some one looking to get Semi Private Proxies for a Affordable Price >> click Here <<

I friend you recommend best buy proxies, since public proxies have access around the world and tend to serve little and are not nothing recommendable to use to work.

You can buy a proxy from affiliated sites where you can get good service I think.
But don't use it for official transactions it may fail you in sometimes.