Just a big tip when at the end of the appointment setting conversation and establishing the next time of telephone contact. Never ask if it’s ok to speak to a prospect in the future or if the prospect is available at a certain time in the future as this makes things too easy for the prospect to just say No or throw you off track. It’s better to take the initiative and refer to a future conversation in a friendly informal way that assumes you will be speaking again. So for example “when we next speak, I’ll give you an update on the question you’ve asked me today”. The prospect feels you are actually helping and there is no over eagerness to call but just feels normal and within reason. Just end the conversation with “speak to you soon” or “ok, we’ll talk soon and you can update me again then!” There is an element of cheekiness in this but if it is within the context, and spirit of the call, it will come over as very natural and not a jolt out of the blue or alarming or out of character. As long as you are congruent, professional and to the point, the prospect will allow you to take control of the conversation as they are busy. Once they know you are doing your job and are knowledgeable can actually help them, they will go your way and not block or question you. It’s easier to stop and apologise (if you really need to) than to explain everything and ask permission. You will get much further. Best of luck and keep it natural!