The replica industry has been around for a long time. Depending on if you have the know-how, this industry can actually be a very profitable one. It is illegal to sell replicas as if they are the real brands in most developed countries. However, if you are honest about what you are selling, and do not copy the brand name exactly, the replica industry is perfectly legal and legitimate. It is also one of the few industries that is recession-proof. The replica watch industry actually recorded an increase in profit during the recession, since most people could no longer afford designer accessories, yet still wanted to maintain their lifestyle.
Some replicas are very poorly made. If you decide to invest in replicas that make it painfully obvious that they are knock-offs, then you probably will not make a lot of money. Replicas need to be made so that they are practically identical to the real thing. Well-made replicas make it impossible to tell the difference between a real thing and a knock-off unless you examine the actual materials of the item up close. If your replicas are almost identical to the real thing, then you could make good money from investing in the replica industry.