I spent a good chunk of my life refusing to pay for things I could realistically do myself - gardening, minor repair jobs around the house, admin stuff etc. Now a little older and wiser, I look back and realise that the benefits of doing those things are probably minor compared to the stress and pressure they put me under, having to add "build that swing set" or "mow that lawn" or "build that bookcase" to my epic list of stuff to do every week.
I've tried to _break_ the habit of automatically going "I could do that, I'm not gonna pay someone else" to looking at how much work something is, and whether it is worth my time to do it or pay someone else to do it, and also try and factor in the unseen costs and the expertise before I decide to take on a project.
Sure, I can put together a kids bike. Easy peasy. But if the shop will charge me $10 to put it together, and it'll save me an hour and a bit of stress, it's worth it.