I build a lot of model buildings to use outside, so I always keep my eyes open for things I can use that will add value to the model but not cost me money. Sunday, one of our Levelor blinds broke. I saved the "wand" that you use to open or close the blade. It's about 24" of white hexagonal plastic rod, perfectly suited for pillars or gate posts. Don't buy a blind to get one of these, but keep your eye out for "trash" with putz house potential.
A few years ago, a neighbor threw away one of those $100 doll house kits that you have to cut all the pieces for and glue together yourself. The "house" was a write-off. But by scrounging the box of parts he had never done anything with, I got a ton of small wooden strips in all sorts of profiles (L-shaped, T-shaped, round on one side, etc.).
In other words, keep your eyes open, and think creatively.
Of course, it's possible to accumulate TOO many future projects.
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