Do brokerages give the brokerage rate in writing?

#1
Just wanted to ask all those who have opened account with any brokerages, do these brokerages give the brokerage charges in writing and make you sign the brokerage charges form as a token of having accepted the charges. What all information is incorporated in the brokerages charges form, this would be helpful to all those who are planning to open account with brokerages.

Also what all forms needs to be signed because so many forms are put in front of you including the Power of Attorney, this Power of Attorney gives the brokerages the power to do buy or sell on your behalf, make loss at your risk. Please advise