Always ask for a token to start the project which can susbsequently be adjusted in your overall fees. Even thouh it is a catch 22 situation and one is always debating in mind with regards to the future benifits of this VIP client, but I believe asking for a value for your service is very professional. If the client is serious about getting the work done, he will not mind the token, though he might not agree to the amount you asked for. keeping all this in mind be prepared to shell out the same token as a client when you are dealing with other professionals!
Try and ask for the token and you will see how ficticious ( clients who are in a habbit of getting work done for free ) will disappear in a blip! your time will be well spent looking out for a real client than just extending your favor! Given said all the above I am not suggesting that you may not accomodate a VIP client in the ways you think are ethically correct towards yourself, profession, and society in general!
After your first meeting with the client you could always follow up with a letter highlighting the scope of work discussed in the meeting and suggest that you could get working on it as soon as you receive an acceptance towards the retainership. YOu could also suggest in the letter that you usually charge x% but you are offering the VIP client a discount.....see how it goes!
Good Luck!