Rather than rounded, soft upholstered arm rest, that your HT-7120 and HT-5040 have, the HT-3300 has wooden arm rests.
You know if we had arrived all honest we'd must say that just about everyone has had the experience before. As well as being able to increase hourly rate, the greater knowledge you have greater likely you are as a way to fulfill your client's needs and offer to the next stage of customer service.