The scourge of making scatter terrain. What's your go-to method?

I've come to a point where I have enough large and medium terrain pieces to cover three gaming tables yet I can't bring myself to make some small scatter terrain. Boxes, bushes, craters, barricades, whatever there is to make the larger pieces come together.

I have these problems:

• I could 3d print them with resin but the density of material and the amount of time it takes absolutely don't seem worth it when I could print minis with that same material and time
• I could craft them but that takes too much time in planning, searching for materials and it's too random if I like them in the end or not
• I could buy pre-made stuff but that has, in my opinion, never been worth the amount it costs
• I could try and re-paint some toys but, again, it's not guaranteed I find suitable ones
• 3d printing masters and making silicone molds to cast them in plaster feels like a good way to get a lot of something (like boxes or barrels) but I hate how much time, materials and tools I need for that plus I don't like how brittle and heavy plaster terrain pieces are
• MDF kits feel great for bigger stuff but the amount of time I have to put into them to make them look good (in my opinion) isn't worth it for smaller stuff and it lacks detail otherwise
• Miss me with GW terrain

What are your methods that are time and money efficient for these kinds of pieces?