Here’s how to get rich.
1. Hire an empty shop for a couple of weeks.
2. Find a sofa/bed/whatever shop that is doing one of these “if you can find it cheaper, we’ll give you double the difference” deals.
3. Buy a sofa/bed/whatever from the shop.
4. Sell it in your shop at 1/2 the price you bought it for.
5. Go back to the sofa/bed/whatever shop and demand double the difference, citing the prices at your shop.
6. Go back to step 3, using the money they just gave you. Keep doing this until you have all their stock in your shop.
Congratulations! You now have a fully stocked shop for the price of one sofa/bed/whatever. Everyone will buy from your shop because that other one is twice the price and never has anything in stock.