Hi Scott,
Allergies and skin problems can be one of the most frustrating problems for pets and their owners. The first thing that should always be done, whether pets are indoors or outdoors, is to make sure flea protection is adequate. There are actual allergy tests that can be done by drawing some blood and any general practitioner should be able to do this, so consider asking your vet about this. The intradermal skin test (the spot test you mention) is much more open to interpretation and is typically only done by specialists. Yes! There are dermatologists for your pets that you can always ask for a referral from your regular veterinarian. If you have an overall good relationship with your veterinarian, then have a discussion with them about your concerns, otherwise, a second opinion does not hurt.
I hope this gives you some direction.
Dr. Ryan Llera