Whilst Private scripts are technically safer, If massed farmed by a bot farm you still run the risk of detection, Now i don't care if your Elon musk and you got spaceX to design a script, the ability to detect third party clients instantly removes all credibility of " Private scripts are safe "
You want to have the mindset that you will get detected, OR, You use an account that has aged 1-2 years and has high stats and is exploiting a bug, E.G the corp beast Bug that allowed someone to farm Corp without taking damage, this went undetected because 1, the account age and 2, no one else was botting those actions. Your most realistic investment would be
A bot Farm that makes accounts automatically after getting banned
Suicide botting
A Private script that does what you want AND mules profits
+ VPN Services ( Because your farm is going to get flagged and mass banned without a VPN, Also buying personal IP Addresses take to much time, Personal IP sales don't guarantee you safety, so you might as well continuously change your IP per account via VPN and expect to get banned, But you are mulling before this happens of course.
A lot of people come to the Black Market of botting thinking that buying a script/ Private script will make them money when in reality, It is much harder then that.
If you are trying to make real cash on the side of your personal life, You will need heavy strategy, Trial and error and at least 1k. No one has the answer for you because why would they? By telling you their methods they are only devaluing their own income. Goodluck out there