TL when to create custom module?

I have arequirement to a add a list of favourite properties linked to the site members.
i.e a registered user with site can mark properties as favourite.

I've already created new table for favourite properties with FK as Userid and PropertyId.
I came acroos this tutorial to create a custom module
http://dev.typolight.org/wiki/1/TutorialsExtension
Do i follow these steps?
What will be the best way to do it and how?

This looks like frontend module. Do you need backend module too?

Yes i need both FE and BE modules so that administrator can see the results, like which is most popular among users etc.

After i add a new folder for module under "system/modules" =>changed config.php => edited the datanase.sql
created table in DB

i go to the typolight/install.php it shows checkboxes to drop the newly added database?