The cellphone business was quite lucrative, I don't know why you guys give me crap for that. The only reason I STOPPED doing that was because I didn't have enough money for the orders that were coming through.
Towards the end, I was pretty much middle-manning transactions from people on EBAY and AMAZON and making about $6.00 - 8.00 on transaction. The problem was the average phone cost like $50 - 70. So if I ended up selling 8 phones in a week, I'd have to pony up about $540 which Amazon would hold for 2-weeks.
I just financially in a position to do that and eventually had to cancel a few transactions and eventually got banned from Amazon. There is definitely money to be made there for those who don't mind coordinating a few things.
Link to my Amazon sales.
The way the scheme works in general is that you have to find a few "niche" phones.
For example, my bread and butter was the HTC Thunderbolt and the Galaxy Fascinate. I found that I could consistently win auctions on eBay for both of these phones for about $10 - 15 cheaper than I could actually sell them on Amazon for (after fees).
So I would literally have listings on Amazon for phones I hadn't won yet. Say I sold 3 Thunderbolts for $80.00 each, I would then go on eBay and win 3 Thunderbolts in the price-range of $65.00 - 75.00. The phones were directly shipped from someone on eBay to someone on Amazon.
I'm not sure if the whole process was legal but I was definitely nickel and diming people throughout the process. The sky is the limit, you just need to know the price points for various phones on both websites; watch listings like crazy; etc.