Second-hand selling has become big business in recent years. While millions of people still use eBay, Facebook Marketplace and Depop to casually pick up bargains or clear out unwanted clothes from time to time, others have switched on to the potential of full-on side hustle.

When you choose the right stuff to sell, you can make a serious profit. But how do you know where to put your cash in the first place? Expert ecommerce accountant and founder of Your Ecommerce Accountant, Ben Sztejka,…