Tough one really mate.

I would say repair it personally and as you say, sell in 6 months.

As to what it's worth, as has been found by some members on here, it's more like what are you willing to accept. Being Spec D does have it's benefits for selling as a whole, so it should in theory go for half decent money, it's just a case of keeping a watching brief on the sites and forums in 6 months for a guide.

Sorry to be so vague