In this project, I have three polygons, see the image below

 1. `"Polygons_From"`, includes input attributes, i.g. `"Value_1"`, `"Value_2"`, `"Value_3"`, and `$area` for each quadrate (on the image there are two types of them).
 2. `"Polygons_To"` polygons for which new values `"Value_1_new"`, `"Value_2_new"`, `"Value_3_new"` need to be defined
 3. `"Border"` defines an area where the calculation should be done.

[![My_input][1]][1]

My task is to transfer values from `"Polygons_From"` into `"Polygons_To"` based on a certain aspect/ratio.

At this point, I am considering `$area`. For instance, for each object in `"Polygons_To"`three values will be calculated as the ratio derived from areas and multiplied by the original values.

But perhaps there are better approaches that will lead me to a much more efficient output.

So, I am asking for a recommendation regarding the technique/workflow that can be applied in QGIS 2.18. Shall I consider only `$area` or there are some other criteria?

Shall I use Virtual Layers?

Moreover, I looking forward to finding some papers that may improve my general understanding of the methodology.

----------

**References:**

 - [Calculating polygon area inside another polygon in QGIS](https://gis.stackexchange.com/questions/240511/calculating-polygon-area-inside-another-polygon-in-qgis)
 - [Combining data from overlapping polygons and assign](https://gis.stackexchange.com/questions/314867/combining-data-from-overlapping-polygons-and-assign)
 - [How to combine data from overlapping polygons?](https://gis.stackexchange.com/questions/43552/how-to-combine-data-from-overlapping-polygons)
 - [Calculating area of polygon inside region?](https://gis.stackexchange.com/questions/120462/calculating-area-of-polygon-inside-region?rq=1)
 - [Calculate proportional area of polygon within another layer's polygon](https://gis.stackexchange.com/questions/214893/calculate-proportional-area-of-polygon-within-another-layers-polygon?rq=1)
 - [Calculating the area of one layer inside area of another layer QGIS](https://gis.stackexchange.com/questions/315029/calculating-the-area-of-one-layer-inside-area-of-another-layer-qgis)

  [1]: https://i.sstatic.net/xE5dv.jpg