Sound Isolation Booth Build on a Budget in Switzerland

In 2024 I built myself a whisper room for singing practice. Here is a detailed vlog with my construction mistakes, costs of tools and materials, and a series of sound checks. I hope it will be helpful to musicians who practice at home and who think about buiding/buying a dedicated music practice space.
🎤 Shure PG58
🎛️ Focusrite Scarlett Solo 1st gen.
💻 Wondershare Filmora 11.8
🎥 GoPro Hero 10
MUSIC
The Painted Night - National Sweetheart
Aurora on the Boulevard - National Sweetheart
In The Wild - National Sweetheart
Tasty Waves - National Sweetheart
The Center Isn't Holding - National Sweetheart
Big Sky Elegy - National Sweetheart
Arm Wrestler - National Sweetheart
For Time To Disappear - Go By Ocean / Ryan McCaffrey
Point Being - Go By Ocean / Ryan McCaffrey
Too Late Now - Go By Ocean / Ryan McCaffrey
Dream It - TrackTribe
Synonyms for search algorithms: vocal booth, ISO booth, soundproof booth, music practice and recording booth, sound insulation booth, noise cancellation.