The amount you need depends on your income, debts and how many people depend on you financially. As both Death and Terminal Illness and Total and Permanent Disablement mean you can no longer earn an income, both insurance types should provide for the same amount.
The cost of your insurance depends on how much insurance you have, your age, gender and job. Premiums are generally more expensive the older you are, if you smoke, have a history of illness or work in a dangerous job.
Example: A 25 year old male who holds his Total and Permanent Disability insurance with Mine Wealth + Wellbeing, works in an underground coal mine and has $800,000 of cover would pay $6.42 per week, or $334 per year, while a 45 year old male would pay $47.85 per week, or $2,488 per year.