Personally I only buy sites that are established (not built to flip in 3 months), have a good product, reasonable revenue, potential to build the revenue up, good content. It also helps if the seller has a good reputation here or @ flippa. the niche does not matter . I have seen loads selling iphone unlocking sites, but to me that trips my BS/Scam radar. Also if someone hyping the site up way too much I walk away
So what is your plan and what kind (niches) of websites, you are looking for in coming days. Yes these are always rock but gaming should be on latest game.
IMO,money making niche is the most easier to sell out. This is mainly due to many reason such as many people look to make money online and looking for tips for this.
It depend on the domain name, the type of domain extension, (in this case .com sell better), the age of the domain name, content, than the traffic, the PR of the site and lot more...
To me I have always seen that pornographic sites are the ones that both make money and sell the fastest. Due to the nature of the site and mass amount of content out there it is easy to gain a lot of content fast and able to sell and purchase ads on other sites that are of the same content and illegal content such as warez. Pornographic sites also gain a lot of traffic also so will raise your sale figures up more so will gain you a greater income. I've never tested this theory out myself but this is based on my reasurch and viewings of the sale section around here. Hope I helped you out.
It depends on how much you want to sell it for....... Earnings, traffic, PR, unique content, SEO and Rank all seem to play a part. But I have sold off autoblogs with only earnings and nothing else and still turned a profit.......