It isn't very clear what your question is. Are you transferring the money from your Wealthbuilder to other funds and you want to do it in small amounts to benegit from "pound cost averaging"? If this is the case then in my opinion you would be wasting your effort because any potential benefits would be outweighed by the fact that you are selling one fund and buying another so the effect is cancelled out. And why does the number of funds lessen the monthly amount? You need to explain things more clearly.