what about brakes? how long the wheel will last? - have not seen any marks on the wheels from brake pads applied

Looks like the brake is on the tire.

Izhar Gafni is to be heartily congratulated. Very clever, and great price (if that really what it will cost at sales time) but a rider WILL feel each and every rut and bump there is no suspension of any kind, and if I'm not mistaken, aren't the tires solid, not inflated.

I see a valve stem on the front wheel so I assume the tires are inflated. It seems like a cool/successful DIY but I'm skeptical about the price. I think materials are low but manufacturing is complex and volume would be low.
The other issue is you can buy a steel bicycle of decent quality for $49 (retail) at Walmart. It is amazing that bicycles are so cheap.
In the US I don't think bicycles would get cheaper even if we had prisoners building them out of cardboard.

For $20 and at approximately 20LBs where can I but one? Really for that price it would be worth it just to try out on my winter commute to save wear and tear on my other bikes.

$20 for 20 miles nice
seriously i doubt this price where do you get ANY 'car timing belt' for under $100? fan belt maybe
20 lbs no way
485 lbs no way
wle

Work of Genius. Next... A Cardboard Car!

Okay, you will never be able to buy one...not for $20.00. Unless, for course, it's manufactured in China. Available at Wal-Mart soon. Put it on layaway.

I've done cardboard things and the glue/epoxy needed to make this work will cost $20. And that doesn't count the labor, etc.
Far better is using laminated wood and glue would last far longer and can be built with some spring in it to soften the ride and make it last longer.
Another would be reusing PET bottles reformed into tubes, etc or used to glue wood plys together and build many things from.

Excellent and deserves encouragement. But of course 20 dollars is unrealistic. And metal manufacturing is vast and ubiquitous. I would love to have bought it for 20 dollars but it can't reach the price mark even in China because of glues, epoxy, ( jerrydd mentions) resins, coatings, safety and finally quality assurance. It looks so cool.