Templates for book authors

Hello I would like to build a multiste where book authors can create their author sites with following steps:
- subscribe
- select a pricing plan
- select a template
- buy
- customize the site (only color, typographie, images)

Witch starter theme is better to build several différent template for author sites with upfront?
Which plugins do I need for that?
Can someone who is not a developper like me can build that or do i need deveopper knowledge?

Thank you for your help.

Acèle