Finding/Buying Coins

If the ebay seller has good feedback, clear and concise pictures, and a 7 day return policy; your usually ok. Buying raw keys on ebay can be scary unless you really know what you are doing. I've gambled quite a few times and have made 100s of purchases on ebay in the last few years. Probably 90% of my collection was purchased on ebay. I only got burned bad on one coin so far; and since then I've made sure to do my homework and have more than made up for the loss. The fact of the matter is that there are unscrupulous sellers who sell overgraded problematic or fake material EVERYWHERE. You will find it at coin shops and coin shows as well. Even some of the top TPG slabs are faked with fake coins, so you have to know your series. Lincolns are a very popular series. Learn the diagnostics of the genuine svdb, 1922 plain, and 1914-d; and you will vastly increase your chances of making a wise purchase with these dates.

I wouldn't say bad things to ebay, just some of their sellers are purposely over graded the merchandise to achieve better selling price. They end up deceiving buyers.
I started buying "loose" UNC coins, I was not doing well. Then I decided to buy only Mint sets in cello. It went very well, since no body can slip in circulated coins. Besides, I calculated, it is cheaper to buy Mint sets (bulk) than "loose" (single) coins. I wouldn't trust what they said about the better grade, I stop at UNC only and bid accordingly. I always got good deal bidding on ebay. For price, I based on Grey list, then refuse to bid higher. If I loose, so be it, there are many others coming, I have time. Lately, this forum help me a lot to save time to look for inexpensive coins right before the bid end. I still loose the bid some time, but let it be, there is always other time.
Since you started with (Circulated) Pennies only, it (especially the shipping's charge) will be too expensive to buy from ebay. My best bet is to selected from bank's roll. To buy only few rolls are too little for the time you spend. It is difficult to get what you want. But if you buy a good amount, you will get more choice, dates, mints and better grade. You don't have to go back to your collection, and check to replace them with a better grade. You select them right there, be done with it. While you are doing that, ask others in the forum who interested to do the same collectively. Ask their list and give your list to them. That way, you have partners in coin hunting, you double, triple, quadruple or even more your chance for a little more time. If your partners in other parts of United States, you will have better chance to get those mints as well. You have more power collectively. I'll be interested to work with you, but it look like I am not qualified yet. Pretty soon, I will be. Request others to joint in.

I just want to get confirmation about raw coin.
It puzzled me, what people means raw coin. But I think, I figure it out. Is it coin without slab PCGS, ANAC, etc? Not even in cello, mint set. Just want to make sure it is correct what I think.

Yes, any coin that has not been graded/slabbed by a Third Party Grader( TPG) would be considered raw.