Tip 1: Find your niche and stick to it
First ask yourself this. What are you knowledgeable about? What are you passionate about selling? You won't be very successful reselling items if you don't have some personal experience or knowledge behind it.
I love anything having to do with electronics or designer items (jeans, shoes or handbags). This mostly comes from my own desire to find deals for myself. I also found I have a pretty good eye when it comes to these particular items and it's simple for me to make a profit.
Tip 2: Set a limit that won't break the bank
Set yourself a limit on what you're willing or capable to spend for something. I personally set myself a limit of no more than $100 on one item, since there's always a possibility it won't sell, or a chance it's fake or broken.
If you're not sure what the item is worth but you feel it's a fairly good bargain, you want to safeguard your investment for the reasons I mentioned. If you're conservative with the items you take a gamble on, you won't get in over your head.
Tip 3: Leave yourself a big profit margin
When you're (re)selling things online, whether it's eBay, Craigslist, Amazon or other sites, you'll rarely ever be able to sell it for the retail price. People shop online to get a bargain, so normally you have to sell the item for 75-50 percent of the original price.
If a pair of designer jeans has a price tag of $220, I can fairly determine they'll sell for about $100-$120 on eBay. This means I need to get them for no more than $50, since I want to double my investment (minus the selling and shipping fees).
My general rule of thumb is to only purchase items that are 75 percent or more off retail. In some unusual cases if the item is really popular or out of stock elsewhere, a bidding war will ensue, which can cause the final price to skyrocket.
Tip 4: Consider time versus money
Personally, I prefer to purchase bigger profit margin items and only spend a little bit of my time reselling them. Some people are very successful at doing the opposite. They find lots of smaller items, with a smaller profit margin but resell them in mass quantities or in bulk. If you want to do this and it works for you, that's great.
But I prefer to assemble and ship the fewest items as possible. This saves me from running back and forth the Post Office or UPS store all the time. Time is just as important as making money, so spend your time wisely and find the best solution that works for you.
Tip 5: Research and remember the time of year
One of the most important things you can do, when looking for items to resell is to research them before you buy. The prices can fluctuate from day to day and from season to season. Be aware of the time of year, and what season is coming up.
If Christmas just ended you will see a massive influx of other people selling unused gift cards and other items online. So the prices and inventory will be very competitive. eBay's mobile app is a great tool to use for finding the current market price for a product. You can either search for current and completed listings, or take a photo of the UPC code to see what the competition is like.
Tip 6: Find quality items to sell
Some of the best places to look for products to resell is at yard sales, consignment shops or places like Salvation Army or Goodwill. You should always inspect the items really well, and if they are electronics, ask to make sure they work or if you can plug them in to test.
You need to think like a business person and purchase quality items, because you are in this to make a profit. Research your item before hand, ask questions and always try to negotiate on the price.
Tip 7: Sometimes you just get lucky
My lucky moment happened when I walked into a used guitar shop, and found a rare six-string guitar. It didn't even have a price-tag on it yet; it was dirty and a little worse for wear. The manager said they just received it and he hadn't even had time to research or process it in their system.
I offered him $100 cash, which he gladly accepted. I paid to have it cleaned, polished and the strings replaced, which only cost me a few bucks. Then I was able to resell it for over $700 on eBay! Sometimes you will just get lucky!
Tip 8: Don't rely on winning the lottery
The bread and butter of my ability to make money online comes from being consistent to follow these rules and not be swept away by the chance of "winning the eBay lottery."
My guitar success story was because I was at the right place at the right time, the market was perfect, and the employee didn't know what he had on his hands. Getting those lucky moments are great, but don't expect them to happen all the time. You have to be smart with your purchases, and be fairly sure you will make your investment (and more) back.
The formula for success
By combining all or some of these tested principles you can create your own success story. Most of my experiences were through trial and error, and there are a few times I got stuck with items I couldn't sell.
There will be ups and downs when you're figuring out your niche and learning the ropes, but above all have fun and enjoy the journey.