If my husband and I both have schizophrenia, what are the chances that our son will have it as well?

Schizophrenia. It is my understanding, that because schizophrenia is associated with a genetic link, that if one parent has schizophrenia, there is about a ten percent chance that an offspring will inherit it. In a case where both parents have schizophrenia, the odds of an offspring having schizophrenia may be as high as 50%.
Good, not absolute. If you are a member of this community, you must be doing very well indeed. So, although your son does have an increased risk secondary to genetics, it is by no means absolute or foregone.