This guide won't tell you how to invest your money, or which coin is the best, or anything like that. It is focused on teaching investors how to rate a coin project prior to the investment decision.
First, i noticed that a lot of people in the forum, especially in the Altcoin section, are rating/following/supporting coins because of their price. It means that the unique argument taken in count for their investment is the price of the coin. Doing this leads most of the people to loose their investments because of a value dump in the best scenario, or to an ICO scam in the worst.
In order to determine wether a coin/project is good for investment, you should consider at least some of these points :
1- The price of a coin isn't determined by the investors, especially in her early days. Because of the low price, the coin developer or a whale (sometimes the exchange itself to draw more volumes) can Pump the coin, in order to simulate a growing attention on the coin, leading other investors to buy it. When the price is high enough, the Dev/Whale/Manipulator proceeds to the Dump, leading to the coin's death. The last part is the result of several Pump/Dump process, as the objective is to keep it attractive long enough to get at least a 25% return. This is the basic P&D schem.
2- The coin/project code is by far the most important criteria to be taken in count, i will explain why some exchanges refuses to list clone coins. First, you should know that the Coin/Project DevTeam size isn't to be taken in count, you can have a single Dev doing a lot of great improvements, as long as he is supported by a community who trusts his work, this is one of the best scenarios for investors, a good developer, backed by a supporting community. The Code aspect is bound to the features introduced, the QT-Wallet isn't to be considered as it is the least important face of a project as many users in the forum can provide you with advanced features in the QT-wallet, you can for example check the work of
OSMIUMCOIN.
So as long as there is no new features in the "Daemon", you should investigate the project prior to invest, because it means that it is either a "ShitCoin" made for P&D schemes, or a "ScamCoin" made for ICO scams, or a "NewbCoin" made by unexperienced users. Note that a few projects with cloned coins are legit, and these have an appreciable value.
3- The community, this point should be taken causiously because it can be easily faked/manipulated, and depends strongly on the funds allowed to it. If you have enough funds you can raise a coin's community with ad campaigns, fake twitter/facebook/linkedin/reddit accounts, so in order to get a more realistic representation of a coin's community, the best is to check them on bitcointalk, if there is a lot of newbie/Jr accounts posting in the thread, then it is a fake community.
So there are 3 aspects to be checked when ever you want to invest for either short term, or long term :
1- The code
2- The community
3- The price
Check these in this order, code, community, price, and you should have a general overview of the coin.
Now how to check for scam projects ? Try to get as many IP addresses as possible and google them first, you will have their location and could check if they have been aleready used in past projects. Check the website with tools like whois.domaintools.com, you will have informations for the domain, you could know if it is a dedicated server or a shared plan, it doesn't really matters, but at least, when scrolling down you can have the ID of the website owner. If it is protected by whoisGuard, then it is possible that the project is a scam, as generally ICO projects discloses their team IDs.
If there is no Team ID disclosure in a ICO project, then it is sure at 50% that it is a scam !
These are the basic detection methods for scam ICOs, ShitCoins, NewbCoins.
So when you talk about a coin, don't talk about the price because it is irrelevant.
-How the exchanges can fake volumes ?
Any developer knows that exchange informations are held in a database, this means that it can be easily changed by a simple query especially if the database is made in order to ease the faking process, so do not trust these informations.
-Why some exchanges refuses to list clone coins ?
Simply because they are regulated, and in this case, they could be guilty of "Money laundering", and in some rare cases "Terrorism financing" or even "Criminal financing". So in order to avoid these troubles who can lead them to jail, they decide not to list clone coins, or shit coins, and they are totally right about this.