Review Web Archive’s versions of the website: Examine the website’s history and how it looked like using the Web Archive. What was it about? What did it offer? This is useful for a variety of different reasons. It could inspire you as to who a good potential buyer might be (by analyzing the website’s content), and it could also signal some red flags in case the domain was being used for anything shady.
However, I'd argue that most people in the business really struggle as they don't understand what makes a good domain name and what's a bad domain name. While I do not work in this field full-time, I can say that I can make a living of it, but it's probably because I don't ask for absurd prices (e.g. randomword247.com domain name for $8000 is just unrealistic and won't happen) and therefore can sell domains easier. 
Since the Buyer pays Escrow.com and not the Seller, Escrow.com can withhold payment until we're satisfied the domain name has been transferred by the Seller. One of the ways Escrow.com does this is by checking the WHOIS database of the appropriate Registrar to make certain it properly reflects the new Buyer's name as the domain name Registrant. Once this has been verified, Escrow.com releases payment to the Seller.
So how do you develop that instinct? NameBio maintains a database of over 500,000 historical domain sales (as of writing this post). They have interesting filtering features by which you can narrow down domains by price range, date sold, keywords and more. Simply sifting through the listings on NameBio long enough will quickly develop your domain appraisal “instinct”.

@ib2 @T-3D I've been a domain investor for over 10 years and have been very successful at it. There's a lot more that goes into it then just registering a domain name and hoping it will sell. You can list your domains on Godaddy auction listings or on premium listings, I've had a lot of success with those. Some good resources are namebio.com, dnjournal.com, namepros.com and others.
Let’s just say for example we wanted this site, crystalgiftsworld.com. It looked good based on our analysis and we’d head over to Snap Names, Nameja is another one and what these service do is they have special technology on their site that allows them to try  to register a domain on your behalf over and over again. Okay? If you tried to do that your IP would get banned, but they have some system where they know how to do it just enough to get the domain, but not enough to get blacklisted.
GoDaddy offers a variety of benefits when you choose to buy or sell your domain with us. We have a unique Auction bidder verification process that protects both buyers and sellers from any kind of fraudulent activity. We also offer a handy Investor mobile app that allows you to watch auctions in real time and view their history (including number of bidders and how much they bid), all from the convenience of your smartphone.

This wonderful piece of information about buying expired domains is simply mind-blowing and I did not know about that before. It is easy for every one to understand about the topic with the pictorial representation. I feel sad that you lost around $400 due to Fake PR, but this article will surely help others save them from any sort of inconvenience.
Many individuals have the habit of collecting attractive domain names but never using them. If so, why not get rid of unused domain names and in the process, make some cash? It is important to understand the whole process of selling domain names. On the outside, the process may look very easy, but unless a trader is well aware of how the whole process works, it is not easy to find a buyer.
That said, my recommended budget for beginners would be $500+. Using this budget you could buy a bunch of high-potential $10 domain names, expired/dropped domain names or a mix of both. It’s very important to invest only what you can afford to lose and treat this as a side hustle till you get the momentum going. As you gain experience, industry expertise and some sales under your belt, you can then consider slowly growing your business into a full-time gig.
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