Best practices for queries and pulling and preparing data

Hi all.

This might seem like a wide question, and I am still fumbling around a bit to get to know how I best can achieve my goal. I am trying to visualize income, expenditures and loan data for a small company renting out 5 homes. Since I am new to PowerBi I do belive I am overthinking and overcomplicating things here.

My main datasource is an Excel Workbook with one workbook sheet of income/expenses per property per year since 2015. (The loan details are in a separate sheet for all properties in the same workbook). This is updated on a monthly basis.

I have created a separate workbook called "Dataset" which through powerquery pulls all data from the years 15-21 in separate sheets. PowerBI pulls data from the different tables in the "Dataset" file. The sheets I already have in PowerBI is marked with green rectangles.

Going forward I was planning on pulling queries directly from the main datasource and adding this to the ones I have created manually in the Dataset file.

So my question is only related to Excel and PowerBi:

Tables:

1. Do I need a table to keep track of all the properties/homes?

2. Does this table need to have HomeID or will the naming e.g. "234/236/Casa" of each home work as ID?

3. Does it make sense to have a separate "Dataset" file or should I just pull all from the main source file. (I did this to prevent clutter in the main source file).

Relationships:

1. Would the suggested relationship in my picture make sense?

Other:

When it comes to expenses, the properties in different countries have very different naming of the expenses. How can I sum and group columns in the best way for visualization? For instance I have the following expense columns:

Netflix | TV | HBO  -> I would like to turn this into "STREAMING" with a total of the aforementioned columns for the visualization.

PS: If there is a better practice for me to use, I will be more than happy to rebuild it all.

I have attached a presentation of the relations ships I have so far (green is already in PowerBi/Red is planned for the near future).