From this ideal list try to find at least ten points which to you are vital, general attributes to either houses or areas. At this stage make this a communal list, involving children if they want to. Expect an animated discussion. It is common in the house buying process for different members of the family to be surprised at what things are important to other members. The object of this exercise is to end up with a document that you shouldn't lose sight of in the sometimes gruelling process to follow. 

From talking to lending institutions to the final negotiation on price it is important not to forget exactly why you wanted a new home in the first instance, keep in mind that as you go through the process of searching your ideas of what you want from a home are likely to be modified.