How long should a couple wait to move in together?

I believe that couples that move in with each other before the one year mark or an engagement is doomed for failure because you don't really know each other that well. After the year mark or an engagement it is okay to start to talk about it and looking. But you did state that you have an autistic child and he doesn't like strangers so for his sake I would hold off longer just to make sure that he can cope with having a male figure in the household.