Tibia Gold a cool down period before they can be recast. Some classes may not have chargeable techniques.
Anybody can buy and sell on Hefei market, but you need to be smart in how you market your goods. To date, I have only used a Lion's Roar to sell an item ONCE, but in retrospect I could have made much better uses of Lion's Roars - I will go on to explain how later on.
First and foremost, you need to know your market. We are all limited to 9 slots for our stands; this means you should be selling 9 desirable goods simultaneously to get a decent throughput on your stand.
It is good to offer a variation of items at varying prices - remember selling 9 items worth 10 million on one stand doesn't mean you'll end up with 90 million by the end of the day. The liklihood is that the more expensive your items, the longer they will take to sell.
As well as keen business acumen, you'll also need to be aware of market prices for many items. Selling items for too much will mean that you'll own them for a lot longer and selling them too cheaply will ultimately result in a lower bank balance for you.