One of the biggest disadvantages of having a C Corporation is taxation.
There are many tax benefits for C Corporations, but the tax disadvantage is that the corporation's
tax at the corporate level, and then after income is spun-off to the shareholders, that
income is taxed to the shareholder level as well.
In some circumstances, you could incur double taxation.
Typically, C Corporations are for larger entities that can take advantage of the tax benefits
to offset the tax disadvantages.