You can find a place to buy and sell most everything at /v 405. I have thin margins on most things. I also made them thinner recently. Also, if you get a customer or supplier to PM me that you referred them, you can get 25r each.
i will have mall for most item selling and buying so i will tell u when it is build so u can come to smp3 (i will tell u the res number)!!!
Not to mention that isn't how things work. First, have products to sell. Then sell them. First, have a shop set up. Then buy things. If you haven't even built your mall, you can neither buy nor sell. If you feel you are capable enough to keep a good stock of key items (sandstone, xp bottles, diamonds, glass), then why not help an existing shop. I'd be perfectly happy paying you a reasonable retail rate on those items, which often go out of stock. You can make the same money, without having to build any shop at all.