There are posts that seem to indicate that someone see a product costing $100 and "realize" they can do it for $50.
I did so ages ago and think that history repeat itself. In the days when my spare time was spent trying to do the above, I got burnt every time. I know now that design is one thing and know-how is another.

Let me state the following "if someone making 1000s of units does it for $100, the likelyhood you can make it work for $50 is infinitessimally small"

Do not let that discourage you from making something, just do not expect it to make you a millionaire but the learning is priceless. If you have youthful energy to pore over a project every night and weekend on the odd chance that you might have a winner, all power to you.

What I am trying with this post is to say "have realistic expectations" the letdown is so much softer when you do.

Yes, it CAN happen. A friend of mine made a lock for a company (read for someone with market knowledge and marketing skills) and when he presented his bill they said "we can not pay you". He agreed to $5 per lock sold and it so happened that, against all expectations, 50.000+ locks were sold.

NOW, if you come up with something new and different and there is a market for it (check first) go full steam

Erik