Now this is thinking outside the box, great ideas!
I did this 20 years ago when I was 18.
We throw money together with a couple of friends, and went to the local electronic store.
Bought brand speakers and radios for cars that were on sale.
Went home and listed the stuff on ebay. After a week everyone of us had its radio or speaker set for free.
Back than we did that to have nice things for "free". But today you could scale that so easily with a few finger tips and your smartphone.
But most people now a days won't put in the work or the humilation to get free stuff they could sell.
I could go on and on where and what to find to make easy money for startup cash.
Take garden / garage sales or fle markets. You can get real steals here.
Matchbox cars in bulk for very cheap, and you got almost every time some collectable oldies in ther that collectors buy for 10 - 50 bucks.
Hell we bought a box with 15 or so nerf guns just because the kids don't play with them anymore for 40 bugs.
All in pretty good shape, but you can sell those easy for 20 -30 bucks each.