This will be one of the most amazing experiences of your life, just be prepared to leave your comfort expectations at home.
That being said, even without the hot showers, the food is fantastic, the group will hopefully be good and as hard as the four day trek is, you will find it more rewarding than just taking a bus to the top.
Also remember that you are helping to support local communities with all the porters that are hired to help you along the way. Go with a positive attitude and you will have the time of your life. Enjoy.