I have installed Version 5.2.0h community successfully. My application is simple and I want to setup the first time right.

My application is:
- contacts from different groups
- need to call and visit these contacts for selling our service
- want to track results and following actions, right and easy after the phone call
- 3 people using the system/database

I tried to setup by myself but can not find out if a contact needs to be related to a account, campaign or a project?

Also wanted to setup an easy to follow task list.
In the task list I see related to and there is no sort function on it and campaign can not be selected.
And an overview who has been called.

What is the most easiest way to update a task or contact data right after the actual call?

This application needs to be setup lean so that the user get not confused with options what are not needed.

I know these are basis questions and I appreciate a lot if you help me to setup the system right.

Thanks!