What service to use to block bots on the site?

Question

firewall

How to deal with bots on the site. which imitate the full behavior of real users, are able to pass Captcha 3, validate SMS and Email through the code, change IP addresses

Found this solution on the market,
https://www.cloudflare.com/products/bot-management/

but, there are features
1 The term of adaptation of the solution is 2 weeks, and we have a project life of 30 days. Reusing machine learning also fails
2. The cost of the solution is very high - $5000/month

Answer 1

Decide on the target audience.
If, for example, the main target audience is in the Russian Federation, then blocking the addresses of China or Latin American countries there would already cut off most of the bots.
Then decide how you distinguish between bots - formalize these signs - and create simple rules for at least the same fail2ban

Answer 2

try to make a javascript captcha where you need to rotate the image to the desired position. change the picture every time. to solve such a captcha, a trained network is required. and yes - do not show in any way that you have calculated the bot. just write down that this is a bot and ignore