custom post templates

Hi.

I am currently looking at developing a website in wordpress that uses quite specific requirements and wondered if these could be done within the wordpress cms.

My client wants to have a site where he can pick what templates he wants to use for a post so for instance, he wants to create an article that consists of 5 pages but each page has its own structure so he picks out of 10 different custom templates 5 that can be used to create a post consisting of different layouts that he can upload text and images in that then creates that 1 post

I wondered before I went ahead and installed wordpress if this sort of thing was entirely possible with custom post templates?

Any help on this would be great before i committed to it.

Thanks,
Mark