If something doesn't sell or buy immediately, don't get RuneScape gold anxious. If it's not buying, it's because you're buying for less than the medium price. And only those who aren't concerned or desperate to cash sell at medium prices. The item is likely to be sold by the end of the day.
If it's not sold then it's likely to be an item that's not popular or you've chosen a bad item, also the rate you've set isn't enough. I wouldn't advise bringing the price down for a day or two after you've posted the offer. Rememberthat merchandising isn't something that happens over night; it take lots of patience.
I would recommend buying everything you need on the g.e. If you're using raw materials such as raw fish, logs and herbs. then I would sell to the public for an established price per item. If you're selling something else (basically not-skilling items) then I'd sell it via the g.e. It might take a while however, this is the most efficient way to go in the sense that it's hard to find someone who is looking for ten dragon platelegs rather than two thousand nature runes.
If you're beginning to merch, I'd suggest at least 10-15m of merchandising. Some general advice: don't be worried about getting into debt in the beginning. It occurs to everyone. When I first startedout, I lost around 6m that first day. Just keep with it and you'll understand the economy and market of the game better. I've opted out of merching in favour of skilling. It's an efficient and time-saving method to make some money.
I'm at level 74. I have already accumulated 200 quest points and I've been completing quests since the age of 15. I would like a recommendation for equipment and inventory (food or potions, for instance.) for questing in general. The things to have around.
Anybody who comes forward. The best thing to do is to have a good supply of various potions and other substances like ropes. The idea of having a set that includes combat equipment of every kind is cheap OSRS gold useful as well. Such as having dragon hide for bosses that include powerful mage attacks as well as mage gear and runes for those times when you need it during some quests.