One point is that basic income would mean an increase in new businesses forming. The problem is that while yes, more people will have the ability to start a business. The increase burdon of taxes and most likely, regulations that go along with it, will make it difficult to move from the startup phase to actually running a profitable company.
Countries like denmark and sweden are great examples of this in action: small companies are scarce,the majority of investors avoid them, and most people either work for the government or a large company.
If you gave a flat distribution of income to a large population set my suspicion is that the money would flow in to housing. Depending on the underlying structure of the particular housing market(s), and the regulatory structure for those market(s) would determine what actually would happen -- better housing, worse housing, the same housing but higher rents, etc.
The other stuff the supply should be elastic enough as to not drive up prices and in some cases would even result in lower prices. Note, if the basic income was applied at a flat rate globally that absolutely wouldn't be the case.