I agree with just taking him to the vet.
There are a lot of different things it could be, and waiting sometimes just makes to worse.
Just a few things that COULD be causing the problem.
Allergies to food, or environmental.
Some dogs are even allergic to fleas.
Different types of mange.
Bacterial skin infection.
Yeast, but that normally starts in ears, or feet before it spreads.
My dogs can even get itchy if their skin is to dry.
Shopping with your husband is like hunting with the game warden.
Experience is what you get, when you didn't get what you wanted.