How many dogs you can handle and properly take care of. That's how many. It also depends what your local laws are - in some places, home owners are only allow 2-3 pets. If you husband thinks that 5 dogs is too many, then he can't handle 5 dogs - so you will need to consider your husband.
I have a small inside dog and he is a lot happier when I got another small dog. So, sometimes it does work out better for a small dog to have a companion dog.
It sounds like you and your husband really need to talk through this to decide what is best for your household.
