It really depends, They could have done 100K in work, or there is always, time to get out, lets be unrealistic about the price. There are still a hand full of people living in 2005.

Of course, the seller can "ask" for any price they want. Will they get a buyer? Not likely if it's overpriced. There can be several valid reasons for the price increase. Perhaps the $307,000 was a "bargain" price, and now the new owner is selling at true market value. Perhaps they made significant improvements. Perhaps the local area has experienced appreciation due to other influences. Without checking comparable properties around this home in its' current condition, no one can say what the current market value should be.