1. "Their is no such thing as life after death"
Reply: First, you have to demonstrate that their isn't. If you don't demonstrate that their isn't then it's your opinion".
2. " Life after death can't be tested scientifically"
This is not true, many psychical researchers have investigated cases that are supportive of the survival hypothesis. Also their has been experiments done to test the survival hypothesis. For example the cross corrspondences, the book tests, the newspaper tests, the proxy sittings, etc.]
3. "Mind is so dependent on the brain that mind cannot exist without the brain"
This is not true, it only seems true if you take the production theory that mind is produced by the brain. The alternative to that would be the transmission theory or filter theory. This view is compataible with psi phenomena and survival of consciousness after death.
4. " Psychics and mediums are out to make money of gullible people, they don't communicate with the dead, they are using cold reading, hot reading and warm reading".
True in many cases but not in all cases.
5. "Psi phenomena and life after death are the same thing"
This one is a common misconception among many materialists. Psi phenomena is about the retrival of information, telepathy for example is the view that you can read someone else's mind.
6. " Life after death is a religious idea"
Not true, their are many people who believe in the possibility of survival and they are not religious.