How much money do you need for E-Trade?

I'm curious to know, how much money do you typically require for investing in E-Trade? Is there a minimum amount that investors need to have in order to start trading on the platform? Additionally, are there any fees or charges associated with opening an account or making trades that potential investors should be aware of? It would be great if you could elaborate on the financial requirements and potential costs involved in utilizing E-Trade for trading purposes.