What you need is
1) cheapest proxies
2) multilogin software
Most of them offer free or cheap trial.
Some of them pretend to be whitehat companies , I guess because hackers also use proxies and they want to avoid them because of legal mess.
You can also get trial and buy from proxies marketplace at bhw.
Gologin has free 7 day trial least leaky next only to mutilogin
After 7 days remove it with an Uninstaller like revo or iobit and install again
Free but leakier