Provided your son is of sound mind and at least 18 years old (younger if married) he can make a will. He may think he doesn't have anything of value but will that always be so? He is likely to acquire property (not just a house) and he may have friends or relatives he would like some possessions to go to.
A will allows him to decide what will go to whom, even if his possessions have sentimental rather than financial value.
It is even more important for your son to have a will if he enters a relationship, even if he doesn't have much property initially as you can build up property quite quickly.
It should be remembered that a will should be reviewed regularly and there are many occasions when a will needs to be updated - for example any will he signs before marriage, if it doesn't contemplate that marriage, will no longer be valid after the marriage and he will die intestate (without a will).
To die intestate means your property will be distributed as prescribed by the Administration Act. A surviving spouse/partner and immediate family usually inherit your property and possessions in proportions set by the act. This may not be what one wishes.
Your lawyer can still handle your estate if you have not made a will, but it can take longer and cost more.
You can arrange an appointment here if you would like to discuss with us the preparation of your will, or for updating a current one if you have had a change in circumstances, we're only too happy to help.