Thanks for the comments!
I personally think this is pretty conventional idea-wise as far as wastelands go, but I did not dare to try anything more fancy (like a huge boat-board etc.).
Here's a list of stuff by different manufacturers that were used in this project in case someone's interested (might miss one or two things):
4D Modelshop (some 1:50 furniture)
Ainsty Castings (resin cars, Utility unit)
Black Cat Bases (litter)
Chinese aquarium plants (ebay)
Crooked Dice Miniatures (Van)
Decors Miniatures (Plastic furniture)
East Riding Miniatures (MDF Boards)
Fenris Games (resin bits via Hasslefree)
Future Warrior Bike
GW Typhus Corrosion paint, Water effect
Pardulon Models (resin parts & scenery)
Pegasus Hobbies (palms, cacti)
Project Zeke (car wrecks, plastic bags)
Reaper Miniatures (Banjo, Bones container & reactor)
Sand
Sc Johnson’s stone & vinyl floor wax
Serious Play (palm trees & vegetation)
Static Grass
Tabletop Arts (resin lids)
Tamiya 1:48 Opel Blitz Tankwagen (bits)
Thomarillion (resin bits, lamps)
Vallejo (Sandy Paste, Pumice, Black Lava, paints, rust pigments, varnish)
Wasteman Miniatures (sofa & armchair)
Zinge Industries (resin bits)
Plastic Putty
Tree bark
Wood strips (hobby store)
Iron wire
Plasticard (Tiles, Corrugated, plain, strips)
MDF Window frames (I can check the company)