As a key tip for beginning this regime, a useful tidbit of advice is to try and stay down in CoC for at least a week before you return to the surface to unload your heaps of loot. The reason for this is that you will want a healthy backstock of items in your 'trader' character's inventory so that you are not pressured into grinding more and returning to the surface more, which can be a real hassle. Avoid selling weapons on your trader unless they are are slotted, blue or green WITH VERY GOOD stats and by 'very good' I mean + 3 or more stats relevant to the weapon. So for instance, a sword with + 1 wisdom and + 1 essence is both worthless and will take a long time to sell, so you are much better off pawning it to an NPC for 17,000 9 dragons gold instead of wasting space and time on your trader's inventory. Be aware that the majority of the drops you will get will be standard weapon drops that are best pawned to an NPC. The best thing to do with these is to take the cash from each weapon sale and use it as pocket money for repairing your clothes and weapons and buying herbs. In the grand scheme of things, it is a very small cash flow and is best used for maintenance rather than totting it up on your accounts sheets.

You will have to be patient a lot of the time, waiting for those good drops to come, but trust me, they will come. Try to focus less on the drops and more on the social aspects of the cave. There will always be players down there to have a laugh with, party with and to become friends with. Let the good times overwrite the bad times, and again trust me on this, there will be times when masked cowards of FC/CS/GL will PK you because it satiates the basest emotions of their testicle-sized brains and there will be times where the good drops just seem to be hiding from you.

Once you have gotten started and the cash is flowing in, maintaining this system is a lot easier than getting started. Just be aware of prices on the market, check around other stands once a week to note down any price fluctuations of items you are selling. Take items that aren't selling off your stand for a while and replace them with other items in your stock as part of a rotation system to keep cash flowing. Also, if there are some items that just won't seem to sell even when you have experimented with their prices endlessly (Sacred Flower meditation and steps tomes are a traders worst nightmare, I know) store them up and every month blow them out of your stand in a sale and lower the prices right down in order to get rid of them (but that NPCs will give you upto 90,000 for some tomes, so never sell for less than an NPC will give you!).