Complex sentence: In some ways they are treated like married couples e.g. when applying for a mortgage or working out child support, but in areas, like property rights, pensions and inheritance, they are treated differently.
Split into simpler sentences: In some ways, such a couple may be treated like a married couple, e.g. when applying for a mortgage or working out child support. However, in some other areas, such as property rights, pensions and inheritance, they are treated differently.