Making a Will is not about wealth it is about making sure that what you want to happen to your estate does happen. It gives you the opportunity to specify such things as who will administer your estate, who will care for your children and who will receive specific items of your property.
If you run your own business don't make your own will.
There are too many problems likely to arise without professional help. For example, if your business is run from office premises does the gift of the business include the premises? Does it carry the goodwill and the stock?
What if you are in partnership and you have a partnership deed that conflicts with your will? It may be a long time since you read the agreement with your partners. It may not say what you remember it saying.
Note that you cannot force your partners to take on a particular person as a partner, so don't try to leave them a new partner in your will.
Business assets attract special relief for inheritance tax purposes. This in itself can create problems in drawing up a will.
For example, if you have a will drawn up by a solicitor and it incorporates a nil rate band discretionary trust, great care is needed to ensure that the trust doesn't end up with far more than the testator intended. For advice on leaving business assets, see a solicitor or accountant.