I'm thinking about getting some extra square meters of lawn in the backyard of my townhouse.
The idea is to demolish the existing wall and then dig out up to about 50 cm from the garage rows (somewhere around there is my property line), and then build a wall from the little fence on the left in the picture, along the garages, and then back the same distance.
It will be a bit more than 1.5 meters deep, and approximately the same height at the highest point (towards the garages), and 30 cm at the lowest point (start and end).
What should I consider?
One thing is to make sure the garages don't collapse onto the property or get undermined. Drainage is probably another consideration.