First, my answer for this is not what it would be if I were younger and trying to build a business, I'm 74 and only take calls for Monday through Wednesday, max. 3 calls per day. I have been surprised at how long people will wait for service. Anyway, I don't want to carry much inventory as I probably will completely retire soon. About all I carry on the truck are dryer and range (coil) elements, Bearing kit for Cabrio and Bravos, actuator, cam kit and capacitors for VMWs, defrost timers and thermostats. There are 2 parts distributors I can access within about 15 miles of most of my calls, so that helps!