Honestly, if he's having vision tracking issues as well as auditory processing disorder, learnign to read is going to be physically painful and supremely frustrating. If you can't afford vision therapy right now (which I totally understand), I would probably back off with trying to teach him to read for the time being. Could the vision therapist design a home program for you to work with him on? But I wouldn't push something that's likely to generate little progress and great frustration for both of you! If you wait a bit and later can afford the vision therapy, then work on remediation, it will be far less frustrating and more successful, increasing the likelihood that he will enjoy reading.