Should I service my 2019 VW Golf GTI before trading it in?

The answer to this question depends entirely on one thing: Are you trading the vehicle in on a new car or selling it privately?

If it’s the former, then the trade-in value won’t be too much different regardless of whether it’s had its 100,000km service or not. Dealerships can service a car for a lot less money than they charge you to do it. But if you’re selling privately, the car will be a lot more attractive to a private buyer if the cost of this major service has already been taken care of.