It's just down to how much you value your time (although you could argue the time spent taking to garage, waiting for it to be done and going home/work is longer than doing it yourself). For the past 20 years I've always changed the oil & filter on my cars (and friends) because I don't mind getting my hands a bit dirty, got all the tools I need and am a right tight fisted old sod. I don't like paying someone money for a job I can do myself. But not everyone is confident of tackling even what a lot of people rate as a simple job, especially if you don't have the tools. I don't think there's a car invented that's not had it's oil changed and posted on YouTube so there's always help online. If it's something you think you're going to do over the course of the next few years you can justify shelling out for a half decent socket set, ramps and oil pan but again it gets back to if you want to spend some of your spare time servicing your own car. Plus, if you did do it you've then got to get rid of the old oil, which is an extra trip to local waste disposal site, another drain on your time. Most people could do most jobs: just need the tools and the confidence to do it.