If I was a potential buyer I'd see someone selling a site just 4 days after launch as a big red flag. Was the developer's confidence in it's potential so low that they chose to take a sum equivalent to 4 months' salaray (assuming they're not 16) rather than ride the wave?
On the other hand, maybe they're on to something - repeatedly build sites with cool design, get a mention on Tech Crunch, and flip.