Referring domains for anchor phrases usually reveals similar information. What you really want to look out for is whether or not the site has been picked up by a spammer in the past. A lot of times these expired domains were dropped, picked up by a website owner who then tried to rank it for keywords like Viagra, Cialis and whatever. You obviously don’t want that kind of domain.
There is NO accurate way to predict the sale of digital assets – if someone wants it, they’ll buy it. For example, those wasting their money on useless .com’s (LLLL’s that have no rhyme or reason) will spend 3x more time and money optimizing their useless name as someone that buys ANY keyword loaded domain (regardless if a TLD or new one). But these individuals who are spending thousands on domains will eventually get stuck with these domains in favor of (you guessed it) the oft forgotten yet highly useful 1-3 keyword domains. Why? Study Google’s algorithm as I have for over a decade, and you’ll figure it out.
There’s an important distinction to make here between domain flipping and website flipping. The latter mainly refers to buying and selling full websites. By full websites, I mean websites that actually have content and more often than not have traffic and revenue. When buying and selling websites, the domain name matters less as the main value there is the content, traffic, revenue, history/reputation, sustainability and growth opportunities. The same can’t be said for domain names where you’re just selling “the name” and hence it’s all that really matters.