Heel Money will buy you a pretty good dog, but it won't buy the wag of a tail. Time, patience, and consistency are the key to this. Some dogs never heel well on the leash much less off, but it there is an overall upside to teaching the heel command.
Many trainers separate the heel with loose leash training and breaking a dog of pulling on the lead.
It could save you time, and money considering some trainers like to split up the two to make more training sessions and ultimately make more money. Here I will save you both. Start by standing on the right side of the dog, have your dog in the sit position. Hold the leash short, to keep him close to you, in your left hand. Starting with your left leg take a large exaggerated step and command heel.