Building a solid domain portfolio is not a piece of cake; it may take you several months or years to achieve this goal but it will definitely be worth it in the end. When you are in the fishing phase, look at the potential of the domain name. Another common strategy used by seasoned domain flippers is to get hold of some high profile domain names and sit on them until they soar in terms of value.
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.
In today's SEO (2015) the answer would be a big no! With changes to the google algorithm and the constant updates panda, penguin, what's next...., much of the "keyword url" power is now gone. While there was a day when it made sense to buy a good named .com and expect instant indexing, not so anymore unless the site is very strong coming in ,which in that case you'll drop a minimum $50k. If you are willing to drop that kind of money and the site has a high domain authority, it might make sense as long as it matches whatever product or service that you're trying to sell. Just my opinion...
There are currently two main types of domain speculators: those that buy domains, build sites around them, and then flip the domain and accompanying website, and then there are those that buy and sell domain names without web sites attached. While both can be very lucrative businesses, the second type is much easier for novices to learn, and as such, shall be the topic of discussion for this article. 
They see a domain’s price tag and they can instantly tell whether it’s under or overvalued. This is probably the most important skill one should have in this industry. Neil Patel has an interesting related quote: “The most important thing to remember when buying sites is that you always make money on the buy, never the sell.” In order to successfully do this, you must be able to spot undervalued domains. This is what will ultimately translate for you into a handsome profit margin when you get the opportunity to resell the domain for its “real value”.