Jacky,
you need to check with a lawyer and see what they say. Alimony is set by the courts and got news for you it is based on his income. If you have been hiding the money then you have hurt yourself. There is also a chance that you may not get it. Child support is also an option, that may not be much either again based on the income that you both have reported. If you contest the amount then the tax man will find out and your both looking at some major fines and possible jiail time.Just remember the childsupport is for the kids not yourself. Yes you can use it for rent, but not for your own use. ie clothing for you, but yes for the kids.
If the business is in your name then you can force him to buy you out, or sell it and then you may have to split the proceeds. Just as with the house. You sell the house and you have to split the proceeds and look at all the taxes you will be paying. an apartment is not the place to put the money , the tax man does not see it that way unless you buy a like priced place. Think it is Fair Gaines Taxes. Not really sure.
Not sure if this will help but I wish you luck