Eric,Without going into too much detail on each line item, at first I use my back of the napkin method with a 40-50% expense ratio.

Are these the only items we need to document?

It is not your responsibility to house this person's items indefinitely in your rental. 

Some items typically needed to qualify for the loan are the following: 1.

What were the biggest line items?

So obviously many of the LPs appear to make these investments not really knowing much detail..

Happy to help answer more detailed questions if you have any and best of luck!

@Steven Catudali don't understand the value that he is bringing... those are all just items you can pay a professional for. 

Also, what others have said, the personal touches on what is in your place (e.g. providing all the essentials instead of having people buy TP, coffee, shampoo, etc.) and the quality of those items (no tattered towels, stained sheets, etc.).  

There are a lot of options out there.Some of the most useful items BiggerPockets members have identified are features that save time so they can spend time working on their next property.