Plus, property management for someone who is busy can be a huge problem. 

What type of businesses are you running?

In your normal course of business, you may choose to try to pass that fee onto the tenant.

I understand some of the pros and cons of going in to business with friends and family but we are both worried of taking the solo leap into rentals.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

For now this is based on trust (no contract between me and her) as we are very long time friends and for me is not really about making money at this point as I'm busy regardless, but more of a help to her.

Justin Noe of Justin Noe real estate and Twin Pillars Investments has been a trusted advisor and business partner throughout this journey as well.

Dealing with this now... 3 business days without a response.

Does it have to be a specific reason to allow them to break the agreed rental contract or it only applies to long term lease? 

Check your state law to verify this is allowed.