once divorce is final, is there anyway to re-open it to contest certain aspects on property?

My ex bought a house while we were together . at time of divorce I could not afford a lawyer and now have discovered that he basically robbed me blind. He is living in that house and paying me nothing for it, I just was kicked out. All we decided in writing was that he will pay me half of the equity when refinanced and he is stalling. am I owed half of the property? does it matter that the divorce is final or can it be re-opened in some way, or taken into court under a different type of case? any help is appreciated thanks so much.Single mom and about to lose my apt, and have no place to go. we have one son who lives with father, and ex also skipped out on final support pmt while son was with me for school last yr. multiple issues. - Is this your question? Add additional information